CVE-2021-47106 (GCVE-0-2021-47106)
Vulnerability from cvelistv5 – Published: 2024-03-04 18:15 – Updated: 2026-08-05 08:46
VLAI
EPSS
VEX
Title
netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()
Summary
In the Linux kernel, the following vulnerability has been resolved:
netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()
We need to use list_for_each_entry_safe() iterator
because we can not access @catchall after kfree_rcu() call.
syzbot reported:
BUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]
BUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]
BUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493
Read of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871
CPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0
Hardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011
Call Trace:
<TASK>
__dump_stack lib/dump_stack.c:88 [inline]
dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106
print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247
__kasan_report mm/kasan/report.c:433 [inline]
kasan_report.cold+0x83/0xdf mm/kasan/report.c:450
nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]
nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]
nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493
__nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626
nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688
notifier_call_chain+0xb5/0x200 kernel/notifier.c:83
blocking_notifier_call_chain kernel/notifier.c:318 [inline]
blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306
netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788
__sock_release+0xcd/0x280 net/socket.c:649
sock_close+0x18/0x20 net/socket.c:1314
__fput+0x286/0x9f0 fs/file_table.c:280
task_work_run+0xdd/0x1a0 kernel/task_work.c:164
tracehook_notify_resume include/linux/tracehook.h:189 [inline]
exit_to_user_mode_loop kernel/entry/common.c:175 [inline]
exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207
__syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]
syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300
do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86
entry_SYSCALL_64_after_hwframe+0x44/0xae
RIP: 0033:0x7f75fbf28adb
Code: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 <48> 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44
RSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003
RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb
RDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003
RBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830
R10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3
R13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032
</TASK>
Allocated by task 8886:
kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38
kasan_set_track mm/kasan/common.c:46 [inline]
set_alloc_info mm/kasan/common.c:434 [inline]
____kasan_kmalloc mm/kasan/common.c:513 [inline]
____kasan_kmalloc mm/kasan/common.c:472 [inline]
__kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522
kasan_kmalloc include/linux/kasan.h:269 [inline]
kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575
kmalloc include/linux/slab.h:590 [inline]
nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline]
nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline]
nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936
nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032
nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513
nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]
nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652
netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]
netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345
netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921
sock_sendmsg_nosec net/
---truncated---
Severity
7.8 (High)
SSVC
Exploitation: none
Automatable: no
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2024-08-15 19:25 UTC
Assigner
References
Impacted products
2 products
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| Linux | Linux |
Affected:
aaa31047a6d25da0fa101da1ed544e1247949b40 , < 9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a
(git)
Affected: aaa31047a6d25da0fa101da1ed544e1247949b40 , < 0f7d9b31ce7abdbb29bf018131ac920c9f698518 (git) |
guessed | |
| Linux | Linux |
Affected:
5.13
Unaffected: 0 , < 5.13 (semver) Unaffected: 5.15.12 , ≤ 5.15.* (semver) Unaffected: 5.16 , ≤ * (original_commit_for_fix) |
guessed |
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{
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"product": "Linux",
"programFiles": [
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"vendor": "Linux",
"versions": [
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{
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{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()\n\nWe need to use list_for_each_entry_safe() iterator\nbecause we can not access @catchall after kfree_rcu() call.\n\nsyzbot reported:\n\nBUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\nRead of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871\n\nCPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\n nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\n nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\n nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\n __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626\n nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688\n notifier_call_chain+0xb5/0x200 kernel/notifier.c:83\n blocking_notifier_call_chain kernel/notifier.c:318 [inline]\n blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306\n netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788\n __sock_release+0xcd/0x280 net/socket.c:649\n sock_close+0x18/0x20 net/socket.c:1314\n __fput+0x286/0x9f0 fs/file_table.c:280\n task_work_run+0xdd/0x1a0 kernel/task_work.c:164\n tracehook_notify_resume include/linux/tracehook.h:189 [inline]\n exit_to_user_mode_loop kernel/entry/common.c:175 [inline]\n exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207\n __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300\n do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f75fbf28adb\nCode: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44\nRSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003\nRAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb\nRDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003\nRBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830\nR10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3\nR13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032\n \u003c/TASK\u003e\n\nAllocated by task 8886:\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\n kasan_set_track mm/kasan/common.c:46 [inline]\n set_alloc_info mm/kasan/common.c:434 [inline]\n ____kasan_kmalloc mm/kasan/common.c:513 [inline]\n ____kasan_kmalloc mm/kasan/common.c:472 [inline]\n __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522\n kasan_kmalloc include/linux/kasan.h:269 [inline]\n kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575\n kmalloc include/linux/slab.h:590 [inline]\n nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline]\n nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline]\n nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936\n nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032\n nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]\n nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652\n netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]\n netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345\n netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921\n sock_sendmsg_nosec net/\n---truncated---"
}
],
"metrics": [
{
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"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The bug is reached through nfnetlink/nftables netlink messages (NFT_MSG_NEWSETELEM then table/set teardown on socket close), which requires local syscall access rather than network packet delivery.\nAC:L - An attacker fully controls setup (create owned table/set with catch-all elements) and trigger (close the netfilter netlink socket or delete the set/table); no victim state or uncontrolled conditions are required.\nPR:L - nfnetlink checks CAP_NET_ADMIN via netlink_net_capable() against the network namespace\u0027s user_ns, so an unprivileged user with user+net namespaces can exercise this path without real root.\nUI:N - The attacker triggers the UAF entirely with their own netlink operations and socket close; no other user action is needed.\nS:U - Successful exploitation yields privilege escalation within the same kernel authority; it does not cross a VM/host or other security-authority boundary.\nC:H - Use-after-free of the kmalloc-64 nft_set_elem_catchall object enables reclaim and disclosure of freed object contents / adjacent kernel memory.\nI:H - Reclaiming the freed catchall lets the attacker control list linkage and catchall-\u003eelem, turning list_del_rcu/nft_set_elem_destroy into arbitrary write/free primitives for code execution.\nA:H - The UAF causes kernel oops/panic on invalid list walks and remains crashable even when not fully exploited for code execution."
}
]
}
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"dateUpdated": "2026-08-05T08:46:01.395Z",
"orgId": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
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"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
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}
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"title": "netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()",
"x_generator": {
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}
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"cveMetadata": {
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"assignerShortName": "Linux",
"cveId": "CVE-2021-47106",
"datePublished": "2024-03-04T18:15:20.190Z",
"dateReserved": "2024-03-04T18:12:48.835Z",
"dateUpdated": "2026-08-05T08:46:01.395Z",
"state": "PUBLISHED"
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"dataVersion": "5.2",
"vulnerability-lookup:meta": {
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"cve": "CVE-2021-47106",
"date": "2026-09-21",
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"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()\n\nWe need to use list_for_each_entry_safe() iterator\nbecause we can not access @catchall after kfree_rcu() call.\n\nsyzbot reported:\n\nBUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\nRead of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871\n\nCPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\n nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\n nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\n nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\n __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626\n nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688\n notifier_call_chain+0xb5/0x200 kernel/notifier.c:83\n blocking_notifier_call_chain kernel/notifier.c:318 [inline]\n blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306\n netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788\n __sock_release+0xcd/0x280 net/socket.c:649\n sock_close+0x18/0x20 net/socket.c:1314\n __fput+0x286/0x9f0 fs/file_table.c:280\n task_work_run+0xdd/0x1a0 kernel/task_work.c:164\n tracehook_notify_resume include/linux/tracehook.h:189 [inline]\n exit_to_user_mode_loop kernel/entry/common.c:175 [inline]\n exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207\n __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300\n do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f75fbf28adb\nCode: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44\nRSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003\nRAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb\nRDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003\nRBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830\nR10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3\nR13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032\n \u003c/TASK\u003e\n\nAllocated by task 8886:\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\n kasan_set_track mm/kasan/common.c:46 [inline]\n set_alloc_info mm/kasan/common.c:434 [inline]\n ____kasan_kmalloc mm/kasan/common.c:513 [inline]\n ____kasan_kmalloc mm/kasan/common.c:472 [inline]\n __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522\n kasan_kmalloc include/linux/kasan.h:269 [inline]\n kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575\n kmalloc include/linux/slab.h:590 [inline]\n nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline]\n nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline]\n nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936\n nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032\n nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]\n nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652\n netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]\n netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345\n netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921\n sock_sendmsg_nosec net/\n---truncated---"
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nf_tables: corrige use-after-free en nft_set_catchall_destroy() Necesitamos usar el iterador list_for_each_entry_safe() porque no podemos acceder a @catchall despu\u00e9s de la llamada a kfree_rcu(). syzbot inform\u00f3: ERROR: KASAN: use-after-free en nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [en l\u00ednea] ERROR: KASAN: use-after-free en nft_set_destroy net/netfilter/nf_tables_api.c:4504 [en l\u00ednea] ERROR : KASAN: use-after-free en nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff8880716e5b80 por tarea syz-executor.3/8871 CPU: 1 PID: 8871 Comm: syz-executor .3 No contaminado 5.16.0-rc5-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Seguimiento de llamadas: __dump_stack lib/dump_stack.c:88 [en l\u00ednea] dump_stack_lvl +0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [en l\u00ednea] kasan_report.cold+0x83/ 0xdf mm/kasan/report.c:450 nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [en l\u00ednea] nft_set_destroy net/netfilter/nf_tables_api.c:4504 [en l\u00ednea] nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_a foto.c:4493 __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626 nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 blocking_notifier_call_chain kernel/ notificador.c:318 [en l\u00ednea ] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306 netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c: 1314 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [en l\u00ednea] exit_to_user_mode_loop kernel/entry/common.c:175 [en l\u00ednea ] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [en l\u00ednea] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/ 0xb0 arco/x86 /entry/common.c:86 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f75fbf28adb C\u00f3digo: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u0026lt;48\u0026gt; 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffd8da7ec10 EFLAGS: 0000 0293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb RDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 00000000000000003 RBP: 00007f75fc08a960 R08: 000000 0000000000 R09: 00007f75fc08e830 R10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3 R13: 00007ffd8da7ed10 R14: 00007f75fc0 88f60 R15: 0000000000000032 Asignado por la tarea 8886 : kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [en l\u00ednea] set_alloc_info mm/kasan/common.c:434 [en l\u00ednea] ____kasan_kmalloc mm/kasan/common.c: 513 [en l\u00ednea] ____kasan_kmalloc mm/kasan/common.c:472 [en l\u00ednea] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:269 [en l\u00ednea] kmem_cache_alloc_trace+0x1ea/0x4a0 mm /slab.c:3575 kmalloc include/linux/slab.h:590 [en l\u00ednea] nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [en l\u00ednea] nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [en l\u00ednea] nft_add_set_elem+0x232e/0 x2f40 net/netfilter/nf_tables_api.c:5936 nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032 nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513 nfnetlink_rcv_skb_batch net/netfilter/ nfnetlink.c:634 [en l\u00ednea] nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [en l\u00ednea]---truncado---"
}
],
"id": "CVE-2021-47106",
"lastModified": "2024-11-21T06:35:24.633",
"published": "2024-03-04T19:15:18.750",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Undergoing Analysis"
},
"nvd": {
"cve": {
"affected": [
{
"affectedData": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/netfilter/nf_tables_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a",
"status": "affected",
"version": "aaa31047a6d25da0fa101da1ed544e1247949b40",
"versionType": "git"
},
{
"lessThan": "0f7d9b31ce7abdbb29bf018131ac920c9f698518",
"status": "affected",
"version": "aaa31047a6d25da0fa101da1ed544e1247949b40",
"versionType": "git"
}
]
},
{
"defaultStatus": "affected",
"product": "Linux",
"programFiles": [
"net/netfilter/nf_tables_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"status": "affected",
"version": "5.13"
},
{
"lessThan": "5.13",
"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
"lessThanOrEqual": "5.15.*",
"status": "unaffected",
"version": "5.15.12",
"versionType": "semver"
},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "5.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67"
}
],
"configurations": [
{
"nodes": [
{
"cpeMatch": [
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"matchCriteriaId": "164CFFE2-DFF5-4AA3-B0D8-BDA39E712F48",
"versionEndExcluding": "5.15.12",
"versionStartIncluding": "5.13",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc1:*:*:*:*:*:*",
"matchCriteriaId": "357AA433-37E8-4323-BFB2-3038D6E4B414",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc2:*:*:*:*:*:*",
"matchCriteriaId": "A73429BA-C2D9-4D0C-A75F-06A1CA8B3983",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc3:*:*:*:*:*:*",
"matchCriteriaId": "F621B5E3-E99D-49E7-90B9-EC3B77C95383",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc4:*:*:*:*:*:*",
"matchCriteriaId": "F7BFDCAA-1650-49AA-8462-407DD593F94F",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc5:*:*:*:*:*:*",
"matchCriteriaId": "6EC9882F-866D-4ACB-8FBC-213D8D8436C8",
"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:5.16:rc6:*:*:*:*:*:*",
"matchCriteriaId": "8A0915FE-A4AA-4C94-B783-CF29D81E7E54",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"cveTags": [],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()\n\nWe need to use list_for_each_entry_safe() iterator\nbecause we can not access @catchall after kfree_rcu() call.\n\nsyzbot reported:\n\nBUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\nRead of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871\n\nCPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\n nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\n nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\n nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\n __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626\n nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688\n notifier_call_chain+0xb5/0x200 kernel/notifier.c:83\n blocking_notifier_call_chain kernel/notifier.c:318 [inline]\n blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306\n netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788\n __sock_release+0xcd/0x280 net/socket.c:649\n sock_close+0x18/0x20 net/socket.c:1314\n __fput+0x286/0x9f0 fs/file_table.c:280\n task_work_run+0xdd/0x1a0 kernel/task_work.c:164\n tracehook_notify_resume include/linux/tracehook.h:189 [inline]\n exit_to_user_mode_loop kernel/entry/common.c:175 [inline]\n exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207\n __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300\n do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f75fbf28adb\nCode: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44\nRSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003\nRAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb\nRDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003\nRBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830\nR10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3\nR13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032\n \u003c/TASK\u003e\n\nAllocated by task 8886:\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\n kasan_set_track mm/kasan/common.c:46 [inline]\n set_alloc_info mm/kasan/common.c:434 [inline]\n ____kasan_kmalloc mm/kasan/common.c:513 [inline]\n ____kasan_kmalloc mm/kasan/common.c:472 [inline]\n __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522\n kasan_kmalloc include/linux/kasan.h:269 [inline]\n kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575\n kmalloc include/linux/slab.h:590 [inline]\n nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline]\n nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline]\n nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936\n nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032\n nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]\n nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652\n netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]\n netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345\n netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921\n sock_sendmsg_nosec net/\n---truncated---"
},
{
"lang": "es",
"value": "En el kernel de Linux, se ha resuelto la siguiente vulnerabilidad: netfilter: nf_tables: corrige use-after-free en nft_set_catchall_destroy() Necesitamos usar el iterador list_for_each_entry_safe() porque no podemos acceder a @catchall despu\u00e9s de la llamada a kfree_rcu(). syzbot inform\u00f3: ERROR: KASAN: use-after-free en nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [en l\u00ednea] ERROR: KASAN: use-after-free en nft_set_destroy net/netfilter/nf_tables_api.c:4504 [en l\u00ednea] ERROR : KASAN: use-after-free en nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493 Lectura de tama\u00f1o 8 en la direcci\u00f3n ffff8880716e5b80 por tarea syz-executor.3/8871 CPU: 1 PID: 8871 Comm: syz-executor .3 No contaminado 5.16.0-rc5-syzkaller #0 Nombre del hardware: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011 Seguimiento de llamadas: __dump_stack lib/dump_stack.c:88 [en l\u00ednea] dump_stack_lvl +0xcd/0x134 lib/dump_stack.c:106 print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247 __kasan_report mm/kasan/report.c:433 [en l\u00ednea] kasan_report.cold+0x83/ 0xdf mm/kasan/report.c:450 nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [en l\u00ednea] nft_set_destroy net/netfilter/nf_tables_api.c:4504 [en l\u00ednea] nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_a foto.c:4493 __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626 nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688 notifier_call_chain+0xb5/0x200 kernel/notifier.c:83 blocking_notifier_call_chain kernel/ notificador.c:318 [en l\u00ednea ] blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306 netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788 __sock_release+0xcd/0x280 net/socket.c:649 sock_close+0x18/0x20 net/socket.c: 1314 __fput+0x286/0x9f0 fs/file_table.c:280 task_work_run+0xdd/0x1a0 kernel/task_work.c:164 tracehook_notify_resume include/linux/tracehook.h:189 [en l\u00ednea] exit_to_user_mode_loop kernel/entry/common.c:175 [en l\u00ednea ] exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207 __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [en l\u00ednea] syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300 do_syscall_64+0x42/ 0xb0 arco/x86 /entry/common.c:86 Entry_SYSCALL_64_after_hwframe+0x44/0xae RIP: 0033:0x7f75fbf28adb C\u00f3digo: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u0026lt;48\u0026gt; 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44 RSP: 002b:00007ffd8da7ec10 EFLAGS: 0000 0293 ORIG_RAX: 0000000000000003 RAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb RDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 00000000000000003 RBP: 00007f75fc08a960 R08: 000000 0000000000 R09: 00007f75fc08e830 R10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3 R13: 00007ffd8da7ed10 R14: 00007f75fc0 88f60 R15: 0000000000000032 Asignado por la tarea 8886 : kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38 kasan_set_track mm/kasan/common.c:46 [en l\u00ednea] set_alloc_info mm/kasan/common.c:434 [en l\u00ednea] ____kasan_kmalloc mm/kasan/common.c: 513 [en l\u00ednea] ____kasan_kmalloc mm/kasan/common.c:472 [en l\u00ednea] __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522 kasan_kmalloc include/linux/kasan.h:269 [en l\u00ednea] kmem_cache_alloc_trace+0x1ea/0x4a0 mm /slab.c:3575 kmalloc include/linux/slab.h:590 [en l\u00ednea] nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [en l\u00ednea] nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [en l\u00ednea] nft_add_set_elem+0x232e/0 x2f40 net/netfilter/nf_tables_api.c:5936 nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032 nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513 nfnetlink_rcv_skb_batch net/netfilter/ nfnetlink.c:634 [en l\u00ednea] nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652 netlink_unicast_kernel net/netlink/af_netlink.c:1319 [en l\u00ednea]---truncado---"
}
],
"id": "CVE-2021-47106",
"lastModified": "2026-08-04T10:16:45.977",
"metrics": {
"cvssMetricV31": [
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"type": "Secondary"
},
{
"cvssData": {
"attackComplexity": "LOW",
"attackVector": "LOCAL",
"availabilityImpact": "HIGH",
"baseScore": 7.8,
"baseSeverity": "HIGH",
"confidentialityImpact": "HIGH",
"integrityImpact": "HIGH",
"privilegesRequired": "LOW",
"scope": "UNCHANGED",
"userInteraction": "NONE",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"exploitabilityScore": 1.8,
"impactScore": 5.9,
"source": "nvd@nist.gov",
"type": "Primary"
}
],
"ssvcV203": [
{
"source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"ssvcData": {
"id": "CVE-2021-47106",
"options": [
{
"exploitation": "none"
},
{
"automatable": "no"
},
{
"technicalImpact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-08-15T19:25:52.257046Z",
"version": "2.0.3"
}
}
]
},
"published": "2024-03-04T19:15:18.750",
"references": [
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
},
{
"source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
},
{
"source": "af854a3a-2127-422b-91ae-364da2661108",
"tags": [
"Patch"
],
"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
}
],
"sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
"vulnStatus": "Modified",
"weaknesses": [
{
"description": [
{
"lang": "en",
"value": "CWE-416"
}
],
"source": "nvd@nist.gov",
"type": "Primary"
}
]
}
},
"redhat_vex": {
"aggregate_severity": "Moderate",
"current_release_date": "2026-08-04T20:06:08+00:00",
"cve": "CVE-2021-47106",
"id": "CVE-2021-47106",
"initial_release_date": "2021-01-01T00:00:00+00:00",
"product_status:known_affected": "44",
"product_status:known_not_affected": "154",
"source": "Red Hat CSAF VEX",
"status": "final",
"title": "kernel: netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()",
"url": "https://security.access.redhat.com/data/csaf/v2/vex/2021/cve-2021-47106.json",
"version": "3"
},
"suse_vex": {
"aggregate_severity": "moderate",
"current_release_date": "2026-09-13T00:01:57Z",
"cve": "CVE-2021-47106",
"id": "CVE-2021-47106",
"initial_release_date": "2024-03-06T04:52:27Z",
"product_status:known_affected": "340",
"product_status:known_not_affected": "344",
"product_status:recommended": "288",
"source": "SUSE CSAF VEX",
"status": "interim",
"title": "SUSE CVE CVE-2021-47106",
"url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2021-47106.json",
"version": "56"
},
"vulnrichment": {
"containers": {
"adp": [
{
"providerMetadata": {
"dateUpdated": "2024-08-04T05:24:39.888Z",
"orgId": "af854a3a-2127-422b-91ae-364da2661108",
"shortName": "CVE"
},
"references": [
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a"
},
{
"tags": [
"x_transferred"
],
"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
}
],
"title": "CVE Program Container"
},
{
"metrics": [
{
"other": {
"content": {
"id": "CVE-2021-47106",
"options": [
{
"Exploitation": "none"
},
{
"Automatable": "no"
},
{
"Technical Impact": "partial"
}
],
"role": "CISA Coordinator",
"timestamp": "2024-08-15T19:25:52.257046Z",
"version": "2.0.3"
},
"type": "ssvc"
}
}
],
"providerMetadata": {
"dateUpdated": "2024-08-15T19:25:57.407Z",
"orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
"shortName": "CISA-ADP"
},
"title": "CISA ADP Vulnrichment"
}
],
"cna": {
"affected": [
{
"defaultStatus": "unaffected",
"product": "Linux",
"programFiles": [
"net/netfilter/nf_tables_api.c"
],
"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
{
"lessThan": "9d558e5f0d6fdd0a568f73dceb0b40c4f5012e5a",
"status": "affected",
"version": "aaa31047a6d25da0fa101da1ed544e1247949b40",
"versionType": "git"
},
{
"lessThan": "0f7d9b31ce7abdbb29bf018131ac920c9f698518",
"status": "affected",
"version": "aaa31047a6d25da0fa101da1ed544e1247949b40",
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"repo": "https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git",
"vendor": "Linux",
"versions": [
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"status": "affected",
"version": "5.13"
},
{
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"status": "unaffected",
"version": "0",
"versionType": "semver"
},
{
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"version": "5.15.12",
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},
{
"lessThanOrEqual": "*",
"status": "unaffected",
"version": "5.16",
"versionType": "original_commit_for_fix"
}
]
}
],
"cpeApplicability": [
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"nodes": [
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"versionEndExcluding": "5.15.12",
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"vulnerable": true
},
{
"criteria": "cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*",
"versionEndExcluding": "5.16",
"versionStartIncluding": "5.13",
"vulnerable": true
}
],
"negate": false,
"operator": "OR"
}
]
}
],
"descriptions": [
{
"lang": "en",
"value": "In the Linux kernel, the following vulnerability has been resolved:\n\nnetfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()\n\nWe need to use list_for_each_entry_safe() iterator\nbecause we can not access @catchall after kfree_rcu() call.\n\nsyzbot reported:\n\nBUG: KASAN: use-after-free in nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\nBUG: KASAN: use-after-free in nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\nRead of size 8 at addr ffff8880716e5b80 by task syz-executor.3/8871\n\nCPU: 1 PID: 8871 Comm: syz-executor.3 Not tainted 5.16.0-rc5-syzkaller #0\nHardware name: Google Google Compute Engine/Google Compute Engine, BIOS Google 01/01/2011\nCall Trace:\n \u003cTASK\u003e\n __dump_stack lib/dump_stack.c:88 [inline]\n dump_stack_lvl+0xcd/0x134 lib/dump_stack.c:106\n print_address_description.constprop.0.cold+0x8d/0x2ed mm/kasan/report.c:247\n __kasan_report mm/kasan/report.c:433 [inline]\n kasan_report.cold+0x83/0xdf mm/kasan/report.c:450\n nft_set_catchall_destroy net/netfilter/nf_tables_api.c:4486 [inline]\n nft_set_destroy net/netfilter/nf_tables_api.c:4504 [inline]\n nft_set_destroy+0x3fd/0x4f0 net/netfilter/nf_tables_api.c:4493\n __nft_release_table+0x79f/0xcd0 net/netfilter/nf_tables_api.c:9626\n nft_rcv_nl_event+0x4f8/0x670 net/netfilter/nf_tables_api.c:9688\n notifier_call_chain+0xb5/0x200 kernel/notifier.c:83\n blocking_notifier_call_chain kernel/notifier.c:318 [inline]\n blocking_notifier_call_chain+0x67/0x90 kernel/notifier.c:306\n netlink_release+0xcb6/0x1dd0 net/netlink/af_netlink.c:788\n __sock_release+0xcd/0x280 net/socket.c:649\n sock_close+0x18/0x20 net/socket.c:1314\n __fput+0x286/0x9f0 fs/file_table.c:280\n task_work_run+0xdd/0x1a0 kernel/task_work.c:164\n tracehook_notify_resume include/linux/tracehook.h:189 [inline]\n exit_to_user_mode_loop kernel/entry/common.c:175 [inline]\n exit_to_user_mode_prepare+0x27e/0x290 kernel/entry/common.c:207\n __syscall_exit_to_user_mode_work kernel/entry/common.c:289 [inline]\n syscall_exit_to_user_mode+0x19/0x60 kernel/entry/common.c:300\n do_syscall_64+0x42/0xb0 arch/x86/entry/common.c:86\n entry_SYSCALL_64_after_hwframe+0x44/0xae\nRIP: 0033:0x7f75fbf28adb\nCode: 0f 05 48 3d 00 f0 ff ff 77 45 c3 0f 1f 40 00 48 83 ec 18 89 7c 24 0c e8 63 fc ff ff 8b 7c 24 0c 41 89 c0 b8 03 00 00 00 0f 05 \u003c48\u003e 3d 00 f0 ff ff 77 35 44 89 c7 89 44 24 0c e8 a1 fc ff ff 8b 44\nRSP: 002b:00007ffd8da7ec10 EFLAGS: 00000293 ORIG_RAX: 0000000000000003\nRAX: 0000000000000000 RBX: 0000000000000004 RCX: 00007f75fbf28adb\nRDX: 00007f75fc08e828 RSI: ffffffffffffffff RDI: 0000000000000003\nRBP: 00007f75fc08a960 R08: 0000000000000000 R09: 00007f75fc08e830\nR10: 00007ffd8da7ed10 R11: 0000000000000293 R12: 00000000002067c3\nR13: 00007ffd8da7ed10 R14: 00007f75fc088f60 R15: 0000000000000032\n \u003c/TASK\u003e\n\nAllocated by task 8886:\n kasan_save_stack+0x1e/0x50 mm/kasan/common.c:38\n kasan_set_track mm/kasan/common.c:46 [inline]\n set_alloc_info mm/kasan/common.c:434 [inline]\n ____kasan_kmalloc mm/kasan/common.c:513 [inline]\n ____kasan_kmalloc mm/kasan/common.c:472 [inline]\n __kasan_kmalloc+0xa6/0xd0 mm/kasan/common.c:522\n kasan_kmalloc include/linux/kasan.h:269 [inline]\n kmem_cache_alloc_trace+0x1ea/0x4a0 mm/slab.c:3575\n kmalloc include/linux/slab.h:590 [inline]\n nft_setelem_catchall_insert net/netfilter/nf_tables_api.c:5544 [inline]\n nft_setelem_insert net/netfilter/nf_tables_api.c:5562 [inline]\n nft_add_set_elem+0x232e/0x2f40 net/netfilter/nf_tables_api.c:5936\n nf_tables_newsetelem+0x6ff/0xbb0 net/netfilter/nf_tables_api.c:6032\n nfnetlink_rcv_batch+0x1710/0x25f0 net/netfilter/nfnetlink.c:513\n nfnetlink_rcv_skb_batch net/netfilter/nfnetlink.c:634 [inline]\n nfnetlink_rcv+0x3af/0x420 net/netfilter/nfnetlink.c:652\n netlink_unicast_kernel net/netlink/af_netlink.c:1319 [inline]\n netlink_unicast+0x533/0x7d0 net/netlink/af_netlink.c:1345\n netlink_sendmsg+0x904/0xdf0 net/netlink/af_netlink.c:1921\n sock_sendmsg_nosec net/\n---truncated---"
}
],
"metrics": [
{
"cvssV3_1": {
"baseScore": 7.8,
"baseSeverity": "HIGH",
"vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
"version": "3.1"
},
"scenarios": [
{
"lang": "en",
"value": "AV:L - The bug is reached through nfnetlink/nftables netlink messages (NFT_MSG_NEWSETELEM then table/set teardown on socket close), which requires local syscall access rather than network packet delivery.\nAC:L - An attacker fully controls setup (create owned table/set with catch-all elements) and trigger (close the netfilter netlink socket or delete the set/table); no victim state or uncontrolled conditions are required.\nPR:L - nfnetlink checks CAP_NET_ADMIN via netlink_net_capable() against the network namespace\u0027s user_ns, so an unprivileged user with user+net namespaces can exercise this path without real root.\nUI:N - The attacker triggers the UAF entirely with their own netlink operations and socket close; no other user action is needed.\nS:U - Successful exploitation yields privilege escalation within the same kernel authority; it does not cross a VM/host or other security-authority boundary.\nC:H - Use-after-free of the kmalloc-64 nft_set_elem_catchall object enables reclaim and disclosure of freed object contents / adjacent kernel memory.\nI:H - Reclaiming the freed catchall lets the attacker control list linkage and catchall-\u003eelem, turning list_del_rcu/nft_set_elem_destroy into arbitrary write/free primitives for code execution.\nA:H - The UAF causes kernel oops/panic on invalid list walks and remains crashable even when not fully exploited for code execution."
}
]
}
],
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"url": "https://git.kernel.org/stable/c/0f7d9b31ce7abdbb29bf018131ac920c9f698518"
}
],
"title": "netfilter: nf_tables: fix use-after-free in nft_set_catchall_destroy()",
"x_generator": {
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}
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"cveMetadata": {
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"assignerShortName": "Linux",
"cveId": "CVE-2021-47106",
"datePublished": "2024-03-04T18:15:20.190Z",
"dateReserved": "2024-03-04T18:12:48.835Z",
"dateUpdated": "2026-08-05T08:46:01.395Z",
"state": "PUBLISHED"
},
"dataType": "CVE_RECORD",
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}
}
}
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Experimental. This forecast is provided for visualization only and may change without notice. Do not use it for operational decisions.
Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.
Sightings
| Author | Source | Type | Date | Other |
|---|
Nomenclature
- Seen: The vulnerability was mentioned, discussed, or observed by the user.
- Confirmed: The vulnerability has been validated from an analyst's perspective.
- Published Proof of Concept: A public proof of concept is available for this vulnerability.
- Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
- Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
- Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
- Not confirmed: The user expressed doubt about the validity of the vulnerability.
- Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.
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The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the
vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base
model, served locally by ML-Gateway.
They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.
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Related by attack behaviour
Vulnerabilities whose description is nearest to this one in the vector space of the CIRCL/vulnerability-attack-technique-biencoder model. This is a similarity search over the bi-encoder space (plain cosine), not a classification, and it has no measured accuracy.
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