Common Weakness Enumeration

CWE-476

Allowed

NULL Pointer Dereference

Abstraction: Base · Status: Stable

API response cwe.mitre.org

The product dereferences a pointer that it expects to be valid but is NULL.

6314 vulnerabilities reference this CWE, most recent first.

GHSA-V5C2-F543-4VHM

Vulnerability from github – Published: 2024-08-17 12:30 – Updated: 2024-12-09 15:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

f2fs: fix null reference error when checking end of zone

This patch fixes a potentially null pointer being accessed by is_end_zone_blkaddr() that checks the last block of a zone when f2fs is mounted as a single device.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
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{
  "affected": [],
  "aliases": [
    "CVE-2024-43857"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-08-17T10:15:10Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nf2fs: fix null reference error when checking end of zone\n\nThis patch fixes a potentially null pointer being accessed by\nis_end_zone_blkaddr() that checks the last block of a zone\nwhen f2fs is mounted as a single device.",
  "id": "GHSA-v5c2-f543-4vhm",
  "modified": "2024-12-09T15:31:33Z",
  "published": "2024-08-17T12:30:33Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-43857"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/381cbe85592c78fbaeb3e770e3e9f3bfa3e67efb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/b98777309756ebe15cc9ad4e8ab64bbfaf878a3f"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/c82bc1ab2a8a5e73d9728e80c4c2ed87e8921a38"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V5F8-GC5J-R8RV

Vulnerability from github – Published: 2021-11-19 00:00 – Updated: 2022-10-16 19:00
VLAI
Details

NULL pointer exception in the IPPUSB dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file

Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2021-39920"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2021-11-18T19:15:00Z",
    "severity": "HIGH"
  },
  "details": "NULL pointer exception in the IPPUSB dissector in Wireshark 3.4.0 to 3.4.9 allows denial of service via packet injection or crafted capture file",
  "id": "GHSA-v5f8-gc5j-r8rv",
  "modified": "2022-10-16T19:00:30Z",
  "published": "2021-11-19T00:00:29Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-39920"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/gitlab-org/cves/-/blob/master/2021/CVE-2021-39920.json"
    },
    {
      "type": "WEB",
      "url": "https://gitlab.com/wireshark/wireshark/-/issues/17705"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/A6AJFIYIHS3TYDD2EBYBJ5KKE52X34BJ"
    },
    {
      "type": "WEB",
      "url": "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/YEWTIRMC2MFQBZ2O5M4CJHJM4JPBHLXH"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/202210-04"
    },
    {
      "type": "WEB",
      "url": "https://www.debian.org/security/2021/dsa-5019"
    },
    {
      "type": "WEB",
      "url": "https://www.wireshark.org/security/wnpa-sec-2021-15.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V5FM-W222-68GQ

Vulnerability from github – Published: 2025-05-08 09:30 – Updated: 2025-11-10 18:30
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

tipc: fix NULL pointer dereference in tipc_mon_reinit_self()

syzbot reported:

tipc: Node number set to 1055423674 Oops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI KASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007] CPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full) Hardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014 Workqueue: events tipc_net_finalize_work RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719 ... RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007 R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010 FS: 0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400 Call Trace: tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140 process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238 process_scheduled_works kernel/workqueue.c:3319 [inline] worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400 kthread+0x3c2/0x780 kernel/kthread.c:464 ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245 ... RIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719 ... RSP: 0018:ffffc9000356fb68 EFLAGS: 00010246 RAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba RDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010 RBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000 R10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007 R13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010 FS: 0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000 CS: 0010 DS: 0000 ES: 0000 CR0: 0000000080050033 CR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0 DR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000 DR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400

There is a racing condition between workqueue created when enabling bearer and another thread created when disabling bearer right after that as follow:

enabling_bearer disabling_bearer
tipc_disc_timeout()
{ bearer_disable()
... {
schedule_work(&tn->work); tipc_mon_delete()
... {
} ...
write_lock_bh(&mon->lock);
mon->self = NULL;
write_unlock_bh(&mon->lock);
...
}
tipc_net_finalize_work() }
{
...
tipc_net_finalize()
{
...
tipc_mon_reinit_self()
{
...
write_lock_bh(&mon->lock);
mon->self->addr = tipc_own_addr(net);
write_unlock_bh(&mon->lock);
...
---truncated---
Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2025-37824"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2025-05-08T07:15:53Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\ntipc: fix NULL pointer dereference in tipc_mon_reinit_self()\n\nsyzbot reported:\n\ntipc: Node number set to 1055423674\nOops: general protection fault, probably for non-canonical address 0xdffffc0000000000: 0000 [#1] SMP KASAN NOPTI\nKASAN: null-ptr-deref in range [0x0000000000000000-0x0000000000000007]\nCPU: 3 UID: 0 PID: 6017 Comm: kworker/3:5 Not tainted 6.15.0-rc1-syzkaller-00246-g900241a5cc15 #0 PREEMPT(full)\nHardware name: QEMU Standard PC (Q35 + ICH9, 2009), BIOS 1.16.3-debian-1.16.3-2~bpo12+1 04/01/2014\nWorkqueue: events tipc_net_finalize_work\nRIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719\n...\nRSP: 0018:ffffc9000356fb68 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba\nRDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010\nRBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000\nR10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007\nR13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010\nFS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\nCall Trace:\n \u003cTASK\u003e\n tipc_net_finalize+0x10b/0x180 net/tipc/net.c:140\n process_one_work+0x9cc/0x1b70 kernel/workqueue.c:3238\n process_scheduled_works kernel/workqueue.c:3319 [inline]\n worker_thread+0x6c8/0xf10 kernel/workqueue.c:3400\n kthread+0x3c2/0x780 kernel/kthread.c:464\n ret_from_fork+0x45/0x80 arch/x86/kernel/process.c:153\n ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245\n \u003c/TASK\u003e\n...\nRIP: 0010:tipc_mon_reinit_self+0x11c/0x210 net/tipc/monitor.c:719\n...\nRSP: 0018:ffffc9000356fb68 EFLAGS: 00010246\nRAX: 0000000000000000 RBX: 0000000000000000 RCX: 000000003ee87cba\nRDX: 0000000000000000 RSI: ffffffff8dbc56a7 RDI: ffff88804c2cc010\nRBP: dffffc0000000000 R08: 0000000000000001 R09: 0000000000000000\nR10: 0000000000000001 R11: 0000000000000000 R12: 0000000000000007\nR13: fffffbfff2111097 R14: ffff88804ead8000 R15: ffff88804ead9010\nFS:  0000000000000000(0000) GS:ffff888097ab9000(0000) knlGS:0000000000000000\nCS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033\nCR2: 00000000f720eb00 CR3: 000000000e182000 CR4: 0000000000352ef0\nDR0: 0000000000000000 DR1: 0000000000000000 DR2: 0000000000000000\nDR3: 0000000000000000 DR6: 00000000fffe0ff0 DR7: 0000000000000400\n\nThere is a racing condition between workqueue created when enabling\nbearer and another thread created when disabling bearer right after\nthat as follow:\n\nenabling_bearer                          | disabling_bearer\n---------------                          | ----------------\ntipc_disc_timeout()                      |\n{                                        | bearer_disable()\n ...                                     | {\n schedule_work(\u0026tn-\u003ework);               |  tipc_mon_delete()\n ...                                     |  {\n}                                        |   ...\n                                         |   write_lock_bh(\u0026mon-\u003elock);\n                                         |   mon-\u003eself = NULL;\n                                         |   write_unlock_bh(\u0026mon-\u003elock);\n                                         |   ...\n                                         |  }\ntipc_net_finalize_work()                 | }\n{                                        |\n ...                                     |\n tipc_net_finalize()                     |\n {                                       |\n  ...                                    |\n  tipc_mon_reinit_self()                 |\n  {                                      |\n   ...                                   |\n   write_lock_bh(\u0026mon-\u003elock);            |\n   mon-\u003eself-\u003eaddr = tipc_own_addr(net); |\n   write_unlock_bh(\u0026mon-\u003elock);          |\n   ...             \n---truncated---",
  "id": "GHSA-v5fm-w222-68gq",
  "modified": "2025-11-10T18:30:31Z",
  "published": "2025-05-08T09:30:25Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2025-37824"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0ceef62a328ce1288598c9242576292671f21e96"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/4d5e1e2d3e9d70beff7beab44fd6ce91405a405e"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5fd464fd24de93d0eca377554bf0ff2548f76f30"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/a3df56010403b2cd26388096ebccf959d23c4dcc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/d63527e109e811ef11abb1c2985048fdb528b4cb"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/dd6cb0a8575b00fbd503e96903184125176f4fa3"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e6613b6d41f4010c4d484cbc7bfca690d8d522a2"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/e79e8e05aa46f90d21023f0ffe6f136ed6a20932"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00030.html"
    },
    {
      "type": "WEB",
      "url": "https://lists.debian.org/debian-lts-announce/2025/05/msg00045.html"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V5J8-4G8Q-9Q2C

Vulnerability from github – Published: 2024-11-22 21:32 – Updated: 2025-09-23 12:31
VLAI
Details

A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow remote attackers who have gained administrator access to launch a denial-of-service (DoS) attack.

We have already fixed the vulnerability in the following versions: QTS 5.2.1.2930 build 20241025 and later QuTS hero h5.2.1.2929 build 20241025 and later

Severity
4.9 (Medium)
CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H
5.1 (Medium)
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-37042"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-11-22T16:15:23Z",
    "severity": "MODERATE"
  },
  "details": "A NULL pointer dereference vulnerability has been reported to affect several QNAP operating system versions. If exploited, the vulnerability could allow remote attackers who have gained administrator access to launch a denial-of-service (DoS) attack.\n\nWe have already fixed the vulnerability in the following versions:\nQTS 5.2.1.2930 build 20241025 and later\nQuTS hero h5.2.1.2929 build 20241025 and later",
  "id": "GHSA-v5j8-4g8q-9q2c",
  "modified": "2025-09-23T12:31:11Z",
  "published": "2024-11-22T21:32:14Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-37042"
    },
    {
      "type": "WEB",
      "url": "https://www.qnap.com/en/security-advisory/qsa-24-43"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:N/VI:L/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

GHSA-V5PJ-64CF-6WC9

Vulnerability from github – Published: 2022-01-15 00:00 – Updated: 2022-01-22 00:01
VLAI
Details

Modex v2.11 was discovered to contain a NULL pointer dereference in set_create_id() at xtract.c.

Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2021-46171"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2022-01-14T21:15:00Z",
    "severity": "MODERATE"
  },
  "details": "Modex v2.11 was discovered to contain a NULL pointer dereference in set_create_id() at xtract.c.",
  "id": "GHSA-v5pj-64cf-6wc9",
  "modified": "2022-01-22T00:01:44Z",
  "published": "2022-01-15T00:00:47Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-46171"
    },
    {
      "type": "WEB",
      "url": "https://github.com/nimble-code/Modex/issues/8"
    }
  ],
  "schema_version": "1.4.0",
  "severity": []
}

GHSA-V5R4-G8JP-RVXF

Vulnerability from github – Published: 2024-05-21 15:31 – Updated: 2024-12-24 18:30
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

udf: Fix NULL pointer dereference in udf_symlink function

In function udf_symlink, epos.bh is assigned with the value returned by udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c and returns the value of sb_getblk function that could be NULL. Then, epos.bh is used without any check, causing a possible NULL pointer dereference when sb_getblk fails.

This fix adds a check to validate the value of epos.bh.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2021-47353"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-05-21T15:15:21Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nudf: Fix NULL pointer dereference in udf_symlink function\n\nIn function udf_symlink, epos.bh is assigned with the value returned\nby udf_tgetblk. The function udf_tgetblk is defined in udf/misc.c\nand returns the value of sb_getblk function that could be NULL.\nThen, epos.bh is used without any check, causing a possible\nNULL pointer dereference when sb_getblk fails.\n\nThis fix adds a check to validate the value of epos.bh.",
  "id": "GHSA-v5r4-g8jp-rvxf",
  "modified": "2024-12-24T18:30:49Z",
  "published": "2024-05-21T15:31:43Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2021-47353"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/21bf1414580c36ffc8d8de043beb3508cf812238"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/2f3d9ddd32a28803baa547e6274983b67d5e287c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/3638705ecd5ad2785e996f820121c0ad15ce64b5"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/371566f63cbd0bb6fbb25b8fe9d5798268d35af9"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/5150877e4d99f85057a458daac7cd7c01005d5c6"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/80d505aee6398cf8beb72475c7edcf1733c1c68b"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/aebed6b19e51a34003d998da5ebb1dfdd2cb1d02"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/baea588a42d675e35daeaddd10fbc9700550bc4d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/fa236c2b2d4436d9f19ee4e5d5924e90ffd7bb43"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V66F-JQGM-8687

Vulnerability from github – Published: 2026-03-20 09:32 – Updated: 2026-07-14 15:31
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

net/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit

teql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit through slave devices, but does not update skb->dev to the slave device beforehand.

When a gretap tunnel is a TEQL slave, the transmit path reaches iptunnel_xmit() which saves dev = skb->dev (still pointing to teql0 master) and later calls iptunnel_xmit_stats(dev, pkt_len). This function does:

get_cpu_ptr(dev->tstats)

Since teql_master_setup() does not set dev->pcpu_stat_type to NETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats for teql0, so dev->tstats is NULL. get_cpu_ptr(NULL) computes NULL + __per_cpu_offset[cpu], resulting in a page fault.

BUG: unable to handle page fault for address: ffff8880e6659018 #PF: supervisor write access in kernel mode #PF: error_code(0x0002) - not-present page PGD 68bc067 P4D 68bc067 PUD 0 Oops: Oops: 0002 [#1] SMP KASAN PTI RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89) Call Trace: ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847) __gre_xmit (net/ipv4/ip_gre.c:478) gre_tap_xmit (net/ipv4/ip_gre.c:779) teql_master_xmit (net/sched/sch_teql.c:319) dev_hard_start_xmit (net/core/dev.c:3887) sch_direct_xmit (net/sched/sch_generic.c:347) __dev_queue_xmit (net/core/dev.c:4802) neigh_direct_output (net/core/neighbour.c:1660) ip_finish_output2 (net/ipv4/ip_output.c:237) __ip_finish_output.part.0 (net/ipv4/ip_output.c:315) ip_mc_output (net/ipv4/ip_output.c:369) ip_send_skb (net/ipv4/ip_output.c:1508) udp_send_skb (net/ipv4/udp.c:1195) udp_sendmsg (net/ipv4/udp.c:1485) inet_sendmsg (net/ipv4/af_inet.c:859) __sys_sendto (net/socket.c:2206)

Fix this by setting skb->dev = slave before calling netdev_start_xmit(), so that tunnel xmit functions see the correct slave device with properly allocated tstats.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2026-23277"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-03-20T09:16:13Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nnet/sched: teql: fix NULL pointer dereference in iptunnel_xmit on TEQL slave xmit\n\nteql_master_xmit() calls netdev_start_xmit(skb, slave) to transmit\nthrough slave devices, but does not update skb-\u003edev to the slave device\nbeforehand.\n\nWhen a gretap tunnel is a TEQL slave, the transmit path reaches\niptunnel_xmit() which saves dev = skb-\u003edev (still pointing to teql0\nmaster) and later calls iptunnel_xmit_stats(dev, pkt_len). This\nfunction does:\n\n    get_cpu_ptr(dev-\u003etstats)\n\nSince teql_master_setup() does not set dev-\u003epcpu_stat_type to\nNETDEV_PCPU_STAT_TSTATS, the core network stack never allocates tstats\nfor teql0, so dev-\u003etstats is NULL. get_cpu_ptr(NULL) computes\nNULL + __per_cpu_offset[cpu], resulting in a page fault.\n\n BUG: unable to handle page fault for address: ffff8880e6659018\n #PF: supervisor write access in kernel mode\n #PF: error_code(0x0002) - not-present page\n PGD 68bc067 P4D 68bc067 PUD 0\n Oops: Oops: 0002 [#1] SMP KASAN PTI\n RIP: 0010:iptunnel_xmit (./include/net/ip_tunnels.h:664 net/ipv4/ip_tunnel_core.c:89)\n Call Trace:\n  \u003cTASK\u003e\n  ip_tunnel_xmit (net/ipv4/ip_tunnel.c:847)\n  __gre_xmit (net/ipv4/ip_gre.c:478)\n  gre_tap_xmit (net/ipv4/ip_gre.c:779)\n  teql_master_xmit (net/sched/sch_teql.c:319)\n  dev_hard_start_xmit (net/core/dev.c:3887)\n  sch_direct_xmit (net/sched/sch_generic.c:347)\n  __dev_queue_xmit (net/core/dev.c:4802)\n  neigh_direct_output (net/core/neighbour.c:1660)\n  ip_finish_output2 (net/ipv4/ip_output.c:237)\n  __ip_finish_output.part.0 (net/ipv4/ip_output.c:315)\n  ip_mc_output (net/ipv4/ip_output.c:369)\n  ip_send_skb (net/ipv4/ip_output.c:1508)\n  udp_send_skb (net/ipv4/udp.c:1195)\n  udp_sendmsg (net/ipv4/udp.c:1485)\n  inet_sendmsg (net/ipv4/af_inet.c:859)\n  __sys_sendto (net/socket.c:2206)\n\nFix this by setting skb-\u003edev = slave before calling\nnetdev_start_xmit(), so that tunnel xmit functions see the correct\nslave device with properly allocated tstats.",
  "id": "GHSA-v66f-jqgm-8687",
  "modified": "2026-07-14T15:31:40Z",
  "published": "2026-03-20T09:32:10Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-23277"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-019113.html"
    },
    {
      "type": "WEB",
      "url": "https://cert-portal.siemens.com/productcert/html/ssa-082556.html"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0bad9c86edd22dec4df83c2b29872d66fd8a2ff4"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/0cc0c2e661af418bbf7074179ea5cfffc0a5c466"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/21ea283c2750c8307aa35ee832b0951cc993c27d"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/383493b9940e3d1b5517424081b3e072e20ec43c"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/57c153249143333bbf4ecf927bdf8aa2696ee397"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/59b06d8b9bdb6b64b3c534c18da68bce5ccd31be"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/6b1f563d670162e188a0f2aec39c24b67b106e17"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/81a43e8005366f16e629d8c95dfe05beaa8d36a7"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V683-5725-54RP

Vulnerability from github – Published: 2022-05-17 00:22 – Updated: 2022-05-17 00:22
VLAI
Details

The MSI-X MMIO support in hw/pci/msix.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (NULL pointer dereference and QEMU process crash) by leveraging failure to define the .write method.

Severity
6.0 (Medium)
CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2015-7549"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2017-10-30T14:29:00Z",
    "severity": "MODERATE"
  },
  "details": "The MSI-X MMIO support in hw/pci/msix.c in QEMU (aka Quick Emulator) allows local guest OS privileged users to cause a denial of service (NULL pointer dereference and QEMU process crash) by leveraging failure to define the .write method.",
  "id": "GHSA-v683-5725-54rp",
  "modified": "2022-05-17T00:22:31Z",
  "published": "2022-05-17T00:22:31Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2015-7549"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=1291137"
    },
    {
      "type": "WEB",
      "url": "https://security.gentoo.org/glsa/201602-01"
    },
    {
      "type": "WEB",
      "url": "http://git.qemu.org/?p=qemu.git%3Ba=commit%3Bh=43b11a91dd861a946b231b89b754285"
    },
    {
      "type": "WEB",
      "url": "http://git.qemu.org/?p=qemu.git;a=commit;h=43b11a91dd861a946b231b89b754285"
    },
    {
      "type": "WEB",
      "url": "http://lists.fedoraproject.org/pipermail/package-announce/2016-January/175380.html"
    },
    {
      "type": "WEB",
      "url": "http://www.debian.org/security/2016/dsa-3471"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2015/12/14/2"
    },
    {
      "type": "WEB",
      "url": "http://www.securityfocus.com/bid/80761"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.0/AV:L/AC:L/PR:H/UI:N/S:C/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V6GX-HF69-Q84X

Vulnerability from github – Published: 2024-07-30 09:31 – Updated: 2025-09-26 15:30
VLAI
Details

In the Linux kernel, the following vulnerability has been resolved:

clk: sunxi-ng: common: Don't call hw_to_ccu_common on hw without common

In order to set the rate range of a hw sunxi_ccu_probe calls hw_to_ccu_common() assuming all entries in desc->ccu_clks are contained in a ccu_common struct. This assumption is incorrect and, in consequence, causes invalid pointer de-references.

Remove the faulty call. Instead, add one more loop that iterates over the ccu_clks and sets the rate range, if required.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2024-42100"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2024-07-30T08:15:02Z",
    "severity": "MODERATE"
  },
  "details": "In the Linux kernel, the following vulnerability has been resolved:\n\nclk: sunxi-ng: common: Don\u0027t call hw_to_ccu_common on hw without common\n\nIn order to set the rate range of a hw sunxi_ccu_probe calls\nhw_to_ccu_common() assuming all entries in desc-\u003eccu_clks are contained\nin a ccu_common struct. This assumption is incorrect and, in\nconsequence, causes invalid pointer de-references.\n\nRemove the faulty call. Instead, add one more loop that iterates over\nthe ccu_clks and sets the rate range, if required.",
  "id": "GHSA-v6gx-hf69-q84x",
  "modified": "2025-09-26T15:30:23Z",
  "published": "2024-07-30T09:31:51Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2024-42100"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/14c78d69dbca6a28af14095f639ec4318ec07fdc"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/7a0e2738cb6da5a55c9908dff333600aeb263e07"
    },
    {
      "type": "WEB",
      "url": "https://git.kernel.org/stable/c/ea977d742507e534d9fe4f4d74256f6b7f589338"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}

GHSA-V6MX-FMFW-P682

Vulnerability from github – Published: 2022-05-13 01:24 – Updated: 2022-05-13 01:24
VLAI
Details

crypto/ghash-generic.c in the Linux kernel before 3.1 allows local users to cause a denial of service (NULL pointer dereference and OOPS) or possibly have unspecified other impact by triggering a failed or missing ghash_setkey function call, followed by a (1) ghash_update function call or (2) ghash_final function call, as demonstrated by a write operation on an AF_ALG socket.

Severity
5.5 (Medium)
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
Show details on source website
To clipboard 

{
  "affected": [],
  "aliases": [
    "CVE-2011-4081"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-476"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2012-05-24T23:55:00Z",
    "severity": "MODERATE"
  },
  "details": "crypto/ghash-generic.c in the Linux kernel before 3.1 allows local users to cause a denial of service (NULL pointer dereference and OOPS) or possibly have unspecified other impact by triggering a failed or missing ghash_setkey function call, followed by a (1) ghash_update function call or (2) ghash_final function call, as demonstrated by a write operation on an AF_ALG socket.",
  "id": "GHSA-v6mx-fmfw-p682",
  "modified": "2022-05-13T01:24:59Z",
  "published": "2022-05-13T01:24:59Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2011-4081"
    },
    {
      "type": "WEB",
      "url": "https://github.com/torvalds/linux/commit/7ed47b7d142ec99ad6880bbbec51e9f12b3af74c"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2012:0010"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/errata/RHSA-2012:0350"
    },
    {
      "type": "WEB",
      "url": "https://access.redhat.com/security/cve/CVE-2011-4081"
    },
    {
      "type": "WEB",
      "url": "https://bugzilla.redhat.com/show_bug.cgi?id=749475"
    },
    {
      "type": "WEB",
      "url": "http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git%3Ba=commit%3Bh=7ed47b7d142ec99ad6880bbbec51e9f12b3af74c"
    },
    {
      "type": "WEB",
      "url": "http://git.kernel.org/?p=linux/kernel/git/torvalds/linux-2.6.git;a=commit;h=7ed47b7d142ec99ad6880bbbec51e9f12b3af74c"
    },
    {
      "type": "WEB",
      "url": "http://www.kernel.org/pub/linux/kernel/v3.x/ChangeLog-3.1"
    },
    {
      "type": "WEB",
      "url": "http://www.openwall.com/lists/oss-security/2011/10/27/2"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    }
  ]
}
Mitigation MIT-56
Implementation

For any pointers that could have been modified or provided from a function that can return NULL, check the pointer for NULL before use. When working with a multithreaded or otherwise asynchronous environment, ensure that proper locking APIs are used to lock before the check, and unlock when it has finished [REF-1484].

Mitigation
Requirements

Select a programming language that is not susceptible to these issues.

Mitigation
Implementation

Check the results of all functions that return a value and verify that the value is non-null before acting upon it.

Mitigation
Architecture and Design

Identify all variables and data stores that receive information from external sources, and apply input validation to make sure that they are only initialized to expected values.

Mitigation
Implementation

Explicitly initialize all variables and other data stores, either during declaration or just before the first usage.

No CAPEC attack patterns related to this CWE.

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