CVE-2025-71126 (GCVE-0-2025-71126)

Vulnerability from cvelistv5 – Published: 2026-01-14 15:06 – Updated: 2026-08-05 12:12
VLAI
Title
mptcp: avoid deadlock on fallback while reinjecting
Summary
In the Linux kernel, the following vulnerability has been resolved: mptcp: avoid deadlock on fallback while reinjecting Jakub reported an MPTCP deadlock at fallback time: WARNING: possible recursive locking detected 6.18.0-rc7-virtme #1 Not tainted -------------------------------------------- mptcp_connect/20858 is trying to acquire lock: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280 but task is already holding lock: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0 other info that might help us debug this: Possible unsafe locking scenario: CPU0 ---- lock(&msk->fallback_lock); lock(&msk->fallback_lock); *** DEADLOCK *** May be due to missing lock nesting notation 3 locks held by mptcp_connect/20858: #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0 #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0 #2: ff1100001da18b60 (&msk->fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0 stack backtrace: CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full) Hardware name: Bochs, BIOS Bochs 01/01/2011 Call Trace: <TASK> dump_stack_lvl+0x6f/0xa0 print_deadlock_bug.cold+0xc0/0xcd validate_chain+0x2ff/0x5f0 __lock_acquire+0x34c/0x740 lock_acquire.part.0+0xbc/0x260 _raw_spin_lock_bh+0x38/0x50 __mptcp_try_fallback+0xd8/0x280 mptcp_sendmsg_frag+0x16c2/0x3050 __mptcp_retrans+0x421/0xaa0 mptcp_release_cb+0x5aa/0xa70 release_sock+0xab/0x1d0 mptcp_sendmsg+0xd5b/0x1bc0 sock_write_iter+0x281/0x4d0 new_sync_write+0x3c5/0x6f0 vfs_write+0x65e/0xbb0 ksys_write+0x17e/0x200 do_syscall_64+0xbb/0xfd0 entry_SYSCALL_64_after_hwframe+0x4b/0x53 RIP: 0033:0x7fa5627cbc5e Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 <c9> c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001 RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005 RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000 R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920 R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c The packet scheduler could attempt a reinjection after receiving an MP_FAIL and before the infinite map has been transmitted, causing a deadlock since MPTCP needs to do the reinjection atomically from WRT fallback. Address the issue explicitly avoiding the reinjection in the critical scenario. Note that this is the only fallback critical section that could potentially send packets and hit the double-lock.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Assigner
References
Impacted products
Vendor Product Version CPE status
Linux Linux Affected: 5586518bec27666c747cd52aabb62d485686d0bf , < 0107442e82c0f8d6010e07e6030741c59c520d6e (git)
Affected: 75a4c9ab8a7af0d76b31ccd1188ed178c38b35d2 , < 252892d5a6a2f163ce18f32716e46fa4da7d4e79 (git)
Affected: 54999dea879fecb761225e28f274b40662918c30 , < 0ca9fb4335e726dab4f23b3bfe87271d8f005f41 (git)
Affected: f8a1d9b18c5efc76784f5a326e905f641f839894 , < 50f47c02be419bf0a3ae94c118addf67beef359f (git)
Affected: f8a1d9b18c5efc76784f5a326e905f641f839894 , < ffb8c27b0539dd90262d1021488e7817fae57c42 (git)
Affected: 1d82a8fe6ee4afdc92f4e8808c9dad2a6095bbc5 (git)
Affected: 6.1.149 , < 6.1.160 (semver)
Affected: 6.6.101 , < 6.6.120 (semver)
Affected: 6.12.40 , < 6.12.64 (semver)
Affected: 6.15.8 , < 6.16 (semver)
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Linux Linux Affected: 6.16
Unaffected: 0 , < 6.16 (semver)
Unaffected: 6.1.160 , ≤ 6.1.* (semver)
Unaffected: 6.6.120 , ≤ 6.6.* (semver)
Unaffected: 6.12.64 , ≤ 6.12.* (semver)
Unaffected: 6.18.3 , ≤ 6.18.* (semver)
Unaffected: 6.19 , ≤ * (original_commit_for_fix)
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          "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: avoid deadlock on fallback while reinjecting\n\nJakub reported an MPTCP deadlock at fallback time:\n\n WARNING: possible recursive locking detected\n 6.18.0-rc7-virtme #1 Not tainted\n --------------------------------------------\n mptcp_connect/20858 is trying to acquire lock:\n ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280\n\n but task is already holding lock:\n ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n other info that might help us debug this:\n  Possible unsafe locking scenario:\n\n        CPU0\n        ----\n   lock(\u0026msk-\u003efallback_lock);\n   lock(\u0026msk-\u003efallback_lock);\n\n  *** DEADLOCK ***\n\n  May be due to missing lock nesting notation\n\n 3 locks held by mptcp_connect/20858:\n  #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0\n  #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0\n  #2: ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n stack backtrace:\n CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full)\n Hardware name: Bochs, BIOS Bochs 01/01/2011\n Call Trace:\n  \u003cTASK\u003e\n  dump_stack_lvl+0x6f/0xa0\n  print_deadlock_bug.cold+0xc0/0xcd\n  validate_chain+0x2ff/0x5f0\n  __lock_acquire+0x34c/0x740\n  lock_acquire.part.0+0xbc/0x260\n  _raw_spin_lock_bh+0x38/0x50\n  __mptcp_try_fallback+0xd8/0x280\n  mptcp_sendmsg_frag+0x16c2/0x3050\n  __mptcp_retrans+0x421/0xaa0\n  mptcp_release_cb+0x5aa/0xa70\n  release_sock+0xab/0x1d0\n  mptcp_sendmsg+0xd5b/0x1bc0\n  sock_write_iter+0x281/0x4d0\n  new_sync_write+0x3c5/0x6f0\n  vfs_write+0x65e/0xbb0\n  ksys_write+0x17e/0x200\n  do_syscall_64+0xbb/0xfd0\n  entry_SYSCALL_64_after_hwframe+0x4b/0x53\n RIP: 0033:0x7fa5627cbc5e\n Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 \u003cc9\u003e c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa\n RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001\n RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e\n RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005\n RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920\n R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c\n\nThe packet scheduler could attempt a reinjection after receiving an\nMP_FAIL and before the infinite map has been transmitted, causing a\ndeadlock since MPTCP needs to do the reinjection atomically from WRT\nfallback.\n\nAddress the issue explicitly avoiding the reinjection in the critical\nscenario. Note that this is the only fallback critical section that\ncould potentially send packets and hit the double-lock."
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              "value": "AV:N - MP_FAIL is a peer-supplied TCP option processed through the MPTCP receive path before any application authentication gate ([RFC 8684 \u00a73.7](https://www.rfc-editor.org/rfc/rfc8684.html#section-3.7)). An Internet-facing MPTCP service is therefore remotely reachable.\nAC:L - A peer can TCP-ACK outstanding bytes while omitting the DSS Data ACK and carrying MP_FAIL, leaving an MPTCP fragment pending after the TCP queue becomes empty; the normal retransmission timer then reaches the nested-lock path. The peer controls the ACK, MP_FAIL, and timing, so no uncontrollable race is required.\nPR:N - No capability, local account, or application credential is required; any remote endpoint completing the MPTCP handshake can send MP_FAIL, and its handler performs no privilege or credential check.\nUI:N - No human action is required because network packet processing and the retransmission timer drive the deadlock, with ordinary service output supplying the pending fragment.\nS:U - The vulnerable receive and retransmission paths and the resulting lockup are within the same kernel security authority, without crossing a VM, IOMMU, or sandbox boundary.\nC:N - This is a recursive spinlock acquisition with no out-of-bounds access, use-after-free, or information-disclosure primitive.\nI:N - The path deadlocks while updating fallback and retransmission state but does not corrupt memory or provide a write or control-flow primitive.\nA:H - The retransmission path holds fallback_lock and then re-enters __mptcp_try_fallback() through mptcp_sendmsg_frag(), spinning indefinitely on the same lock ([fix commit](https://git.kernel.org/stable/c/ffb8c27b0539dd90262d1021488e 7817fae57c42)). This can lock a CPU or panic the kernel via watchdog and can be repeated across connections."
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                    "matchCriteriaId": "8F519034-DE85-479C-A073-22A202B0A1BE",
                    "versionEndExcluding": "6.18.3",
                    "versionStartIncluding": "6.16.1",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.16:-:*:*:*:*:*:*",
                    "matchCriteriaId": "6238B17D-C12B-458F-A138-97039BFC4595",
                    "vulnerable": true
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                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc1:*:*:*:*:*:*",
                    "matchCriteriaId": "17B67AA7-40D6-4AFA-8459-F200F3D7CFD1",
                    "vulnerable": true
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                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc2:*:*:*:*:*:*",
                    "matchCriteriaId": "C47E4CC9-C826-4FA9-B014-7FE3D9B318B2",
                    "vulnerable": true
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                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc3:*:*:*:*:*:*",
                    "matchCriteriaId": "F71D92C0-C023-48BD-B3B6-70B638EEE298",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc4:*:*:*:*:*:*",
                    "matchCriteriaId": "13580667-0A98-40CC-B29F-D12790B91BDB",
                    "vulnerable": true
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                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc5:*:*:*:*:*:*",
                    "matchCriteriaId": "CAD1FED7-CF48-47BF-AC7D-7B6FA3C065FC",
                    "vulnerable": true
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                  {
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                    "matchCriteriaId": "3EF854A1-ABB1-4E93-BE9A-44569EC76C0D",
                    "vulnerable": true
                  },
                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc7:*:*:*:*:*:*",
                    "matchCriteriaId": "F5DC0CA6-F0AF-4DDF-A882-3DADB9A886A7",
                    "vulnerable": true
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                  {
                    "criteria": "cpe:2.3:o:linux:linux_kernel:6.19:rc8:*:*:*:*:*:*",
                    "matchCriteriaId": "EB5B7DFC-C36B-45D8-922C-877569FDDF43",
                    "vulnerable": true
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                ],
                "negate": false,
                "operator": "OR"
              }
            ]
          }
        ],
        "cveTags": [],
        "descriptions": [
          {
            "lang": "en",
            "value": "In the Linux kernel, the following vulnerability has been resolved:\n\nmptcp: avoid deadlock on fallback while reinjecting\n\nJakub reported an MPTCP deadlock at fallback time:\n\n WARNING: possible recursive locking detected\n 6.18.0-rc7-virtme #1 Not tainted\n --------------------------------------------\n mptcp_connect/20858 is trying to acquire lock:\n ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280\n\n but task is already holding lock:\n ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n other info that might help us debug this:\n  Possible unsafe locking scenario:\n\n        CPU0\n        ----\n   lock(\u0026msk-\u003efallback_lock);\n   lock(\u0026msk-\u003efallback_lock);\n\n  *** DEADLOCK ***\n\n  May be due to missing lock nesting notation\n\n 3 locks held by mptcp_connect/20858:\n  #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0\n  #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0\n  #2: ff1100001da18b60 (\u0026msk-\u003efallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n stack backtrace:\n CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full)\n Hardware name: Bochs, BIOS Bochs 01/01/2011\n Call Trace:\n  \u003cTASK\u003e\n  dump_stack_lvl+0x6f/0xa0\n  print_deadlock_bug.cold+0xc0/0xcd\n  validate_chain+0x2ff/0x5f0\n  __lock_acquire+0x34c/0x740\n  lock_acquire.part.0+0xbc/0x260\n  _raw_spin_lock_bh+0x38/0x50\n  __mptcp_try_fallback+0xd8/0x280\n  mptcp_sendmsg_frag+0x16c2/0x3050\n  __mptcp_retrans+0x421/0xaa0\n  mptcp_release_cb+0x5aa/0xa70\n  release_sock+0xab/0x1d0\n  mptcp_sendmsg+0xd5b/0x1bc0\n  sock_write_iter+0x281/0x4d0\n  new_sync_write+0x3c5/0x6f0\n  vfs_write+0x65e/0xbb0\n  ksys_write+0x17e/0x200\n  do_syscall_64+0xbb/0xfd0\n  entry_SYSCALL_64_after_hwframe+0x4b/0x53\n RIP: 0033:0x7fa5627cbc5e\n Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05 \u003cc9\u003e c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa\n RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001\n RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e\n RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005\n RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920\n R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c\n\nThe packet scheduler could attempt a reinjection after receiving an\nMP_FAIL and before the infinite map has been transmitted, causing a\ndeadlock since MPTCP needs to do the reinjection atomically from WRT\nfallback.\n\nAddress the issue explicitly avoiding the reinjection in the critical\nscenario. Note that this is the only fallback critical section that\ncould potentially send packets and hit the double-lock."
          },
          {
            "lang": "es",
            "value": "En el kernel de Linux, la siguiente vulnerabilidad ha sido resuelta:\n\nmptcp: evitar interbloqueo en el fallback mientras se reinjecta\n\nJakub inform\u00f3 un interbloqueo MPTCP en el momento del fallback:\n\n WARNING: possible recursive locking detected\n 6.18.0-rc7-virtme #1 Not tainted\n --------------------------------------------\n mptcp_connect/20858 is trying to acquire lock:\n ff1100001da18b60 (\u0026amp;msk-\u0026gt;fallback_lock){+.-.}-{3:3}, at: __mptcp_try_fallback+0xd8/0x280\n\n but task is already holding lock:\n ff1100001da18b60 (\u0026amp;msk-\u0026gt;fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n other info that might help us debug this:\n  Possible unsafe locking scenario:\n\n        CPU0\n        ----\n   lock(\u0026amp;msk-\u0026gt;fallback_lock);\n   lock(\u0026amp;msk-\u0026gt;fallback_lock);\n\n  * DEADLOCK *\n\n  May be due to missing lock nesting notation\n\n 3 locks held by mptcp_connect/20858:\n  #0: ff1100001da18290 (sk_lock-AF_INET){+.+.}-{0:0}, at: mptcp_sendmsg+0x114/0x1bc0\n  #1: ff1100001db40fd0 (k-sk_lock-AF_INET#2){+.+.}-{0:0}, at: __mptcp_retrans+0x2cb/0xaa0\n  #2: ff1100001da18b60 (\u0026amp;msk-\u0026gt;fallback_lock){+.-.}-{3:3}, at: __mptcp_retrans+0x352/0xaa0\n\n stack backtrace:\n CPU: 0 UID: 0 PID: 20858 Comm: mptcp_connect Not tainted 6.18.0-rc7-virtme #1 PREEMPT(full)\n Hardware name: Bochs, BIOS Bochs 01/01/2011\n Call Trace:\n  \n  dump_stack_lvl+0x6f/0xa0\n  print_deadlock_bug.cold+0xc0/0xcd\n  validate_chain+0x2ff/0x5f0\n  __lock_acquire+0x34c/0x740\n  lock_acquire.part.0+0xbc/0x260\n  _raw_spin_lock_bh+0x38/0x50\n  __mptcp_try_fallback+0xd8/0x280\n  mptcp_sendmsg_frag+0x16c2/0x3050\n  __mptcp_retrans+0x421/0xaa0\n  mptcp_release_cb+0x5aa/0xa70\n  release_sock+0xab/0x1d0\n  mptcp_sendmsg+0xd5b/0x1bc0\n  sock_write_iter+0x281/0x4d0\n  new_sync_write+0x3c5/0x6f0\n  vfs_write+0x65e/0xbb0\n  ksys_write+0x17e/0x200\n  do_syscall_64+0xbb/0xfd0\n  entry_SYSCALL_64_after_hwframe+0x4b/0x53\n RIP: 0033:0x7fa5627cbc5e\n Code: 4d 89 d8 e8 14 bd 00 00 4c 8b 5d f8 41 8b 93 08 03 00 00 59 5e 48 83 f8 fc 74 11 c9 c3 0f 1f 80 00 00 00 00 48 8b 45 10 0f 05  c3 83 e2 39 83 fa 08 75 e7 e8 13 ff ff ff 0f 1f 00 f3 0f 1e fa\n RSP: 002b:00007fff1fe14700 EFLAGS: 00000202 ORIG_RAX: 0000000000000001\n RAX: ffffffffffffffda RBX: 0000000000000005 RCX: 00007fa5627cbc5e\n RDX: 0000000000001f9c RSI: 00007fff1fe16984 RDI: 0000000000000005\n RBP: 00007fff1fe14710 R08: 0000000000000000 R09: 0000000000000000\n R10: 0000000000000000 R11: 0000000000000202 R12: 00007fff1fe16920\n R13: 0000000000002000 R14: 0000000000001f9c R15: 0000000000001f9c\n\nEl planificador de paquetes podr\u00eda intentar una reinyecci\u00f3n despu\u00e9s de recibir un MP_FAIL y antes de que se haya transmitido el mapa infinito, causando un interbloqueo ya que MPTCP necesita realizar la reinyecci\u00f3n at\u00f3micamente con respecto al fallback.\n\nAbordar el problema evitando expl\u00edcitamente la reinyecci\u00f3n en el escenario cr\u00edtico. Tenga en cuenta que esta es la \u00fanica secci\u00f3n cr\u00edtica de fallback que podr\u00eda potencialmente enviar paquetes y alcanzar el doble bloqueo."
          }
        ],
        "id": "CVE-2025-71126",
        "lastModified": "2026-07-30T06:24:52.503",
        "metrics": {
          "cvssMetricV31": [
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "NETWORK",
                "availabilityImpact": "HIGH",
                "baseScore": 7.5,
                "baseSeverity": "HIGH",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "NONE",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 3.9,
              "impactScore": 3.6,
              "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
              "type": "Secondary"
            },
            {
              "cvssData": {
                "attackComplexity": "LOW",
                "attackVector": "LOCAL",
                "availabilityImpact": "HIGH",
                "baseScore": 5.5,
                "baseSeverity": "MEDIUM",
                "confidentialityImpact": "NONE",
                "integrityImpact": "NONE",
                "privilegesRequired": "LOW",
                "scope": "UNCHANGED",
                "userInteraction": "NONE",
                "vectorString": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
                "version": "3.1"
              },
              "exploitabilityScore": 1.8,
              "impactScore": 3.6,
              "source": "nvd@nist.gov",
              "type": "Primary"
            }
          ]
        },
        "published": "2026-01-14T15:16:02.317",
        "references": [
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/0107442e82c0f8d6010e07e6030741c59c520d6e"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/0ca9fb4335e726dab4f23b3bfe87271d8f005f41"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/252892d5a6a2f163ce18f32716e46fa4da7d4e79"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/50f47c02be419bf0a3ae94c118addf67beef359f"
          },
          {
            "source": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
            "tags": [
              "Patch"
            ],
            "url": "https://git.kernel.org/stable/c/ffb8c27b0539dd90262d1021488e7817fae57c42"
          }
        ],
        "sourceIdentifier": "416baaa9-dc9f-4396-8d5f-8c081fb06d67",
        "vulnStatus": "Modified",
        "weaknesses": [
          {
            "description": [
              {
                "lang": "en",
                "value": "CWE-667"
              }
            ],
            "source": "nvd@nist.gov",
            "type": "Primary"
          }
        ]
      }
    },
    "redhat_vex": {
      "aggregate_severity": "Moderate",
      "current_release_date": "2026-07-30T08:33:15+00:00",
      "cve": "CVE-2025-71126",
      "id": "CVE-2025-71126",
      "initial_release_date": "2025-01-01T00:00:00+00:00",
      "product_status:known_affected": "184",
      "product_status:known_not_affected": "90",
      "source": "Red Hat CSAF VEX",
      "status": "final",
      "title": "kernel: Linux kernel: Deadlock due to MPTCP packet reinjection during fallback",
      "url": "https://security.access.redhat.com/data/csaf/v2/vex/2025/cve-2025-71126.json",
      "version": "3"
    },
    "suse_vex": {
      "aggregate_severity": "moderate",
      "current_release_date": "2026-09-19T02:02:06Z",
      "cve": "CVE-2025-71126",
      "id": "CVE-2025-71126",
      "initial_release_date": "2026-01-16T00:26:12Z",
      "product_status:first_fixed": "2",
      "product_status:known_affected": "449",
      "product_status:known_not_affected": "312",
      "product_status:recommended": "280",
      "source": "SUSE CSAF VEX",
      "status": "interim",
      "title": "SUSE CVE CVE-2025-71126",
      "url": "https://ftp.suse.com/pub/projects/security/csaf-vex/cve-2025-71126.json",
      "version": "32"
    }
  }
}



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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.

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  • 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.
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  • 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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