CVE-2022-49904

Medium

In the Linux kernel, the following vulnerability has been resolved: net, neigh: Fix null-ptr-deref in neigh_table_clear() When IPv6 module gets initialized but hits an error in the middle, kenel panic with: KASAN: null-ptr-deref in range [0x0000000000000598-0x000000000000059f] CPU: 1 PID: 361 Comm: insmod Hardware name: QEMU Standard PC (i440FX + PIIX, 1996) RIP: 0010:__neigh_ifdown.isra.0+0x24b/0x370 RSP: 0018:ffff888012677908 EFLAGS: 00000202 ... Call Trace: <TASK> neigh_table_clear+0x94/0x2d0 ndisc_cleanup+0x27/0x40 [ipv6] inet6_init+0x21c/0x2cb [ipv6] do_one_initcall+0xd3/0x4d0 do_init_module+0x1ae/0x670 ... Kernel panic - not syncing: Fatal exception When ipv6 initialization fails, it will try to cleanup and calls: neigh_table_clear() neigh_ifdown(tbl, NULL) pneigh_queue_purge(&tbl->proxy_queue, dev_net(dev == NULL)) # dev_net(NULL) triggers null-ptr-deref. Fix it by passing NULL to pneigh_queue_purge() in neigh_ifdown() if dev is NULL, to make kernel not panic immediately.

Package Linux Kernel
Published 2025-05-01
Last modified 2025-10-01
CVSS version 3.1
Patch available
Yes

CVSS 3.1 score

5.5

out of 10
Medium
Attack Vector
Local
Attack Complexity
Low
Privileges Required
Low
User Interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
High
Vector string
CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Weakness type

CWE-476

CVE-2022-49904 is a NULL Pointer Dereference vulnerability

What is NULL Pointer Dereference?

The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. Learn more on MITRE CWE

Affected versions

Linux kernel versions 4.14.292, 4.19.257, 5.4.212, 5.10.141, 5.15.65, 5.19.7, 6.0 and later are affected. Fixed in 4.14.299, 4.19.265, 5.4.224, 5.10.154, 5.15.78, 6.0.8, 6.1 and their respective stable series.

Affected from
≥ 4.14.292 ≥ 4.19.257 ≥ 5.4.212 ≥ 5.10.141 ≥ 5.15.65 ≥ 5.19.7 ≥ 6.0
Fixed in
✓ 4.14.299 4.14.x ✓ 4.19.265 4.19.x ✓ 5.4.224 5.4.x ✓ 5.10.154 5.10.x ✓ 5.15.78 5.15.x ✓ 6.0.8 6.0.x ✓ 6.1

References

The following references provide additional information about CVE-2022-49904 including vendor advisories, patch commits, exploit details, and third-party analysis. Links are sourced from the NIST NVD database.

Frequently asked questions

  • What is CVE-2022-49904?

    CVE-2022-49904 is a Medium severity Linux kernel vulnerability with a CVSS score of 5.5 out of 10 , classified as a NULL Pointer Dereference flaw (CWE-476) . It affects Linux kernel versions from 4.14.292 onward and has been patched in 4.14.299, 4.19.265, 5.4.224 and others. CVE-2022-49904 has not been confirmed as actively exploited and is not listed in the CISA KEV catalog.

  • What is the CVSS score for CVE-2022-49904?

    CVE-2022-49904 has a CVSS score of 5.5 out of 10, rated Medium severity (CVSS 3.1). The vector string is CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H .

  • Is there a patch available for CVE-2022-49904?

    Yes — CVE-2022-49904 has been patched. Fixed versions include 4.14.299, 4.19.265, 5.4.224 and others. If you are running Linux kernel 4.14.292 or later up to the fix versions, apply the relevant patch for your kernel branch.

  • Is CVE-2022-49904 actively exploited?

    No — CVE-2022-49904 has not been confirmed as actively exploited. It is not listed in the CISA Known Exploited Vulnerabilities (KEV) catalog.

  • What is NULL Pointer Dereference (CWE-476)?

    The product dereferences a pointer that it expects to be valid but is NULL, typically causing a crash. View CWE-476 on MITRE CWE →