PT-2025-18621 · Linux+1 · Linux Kernel+1

Published 2025-05-01 · Updated 2025-05-02 · CVE-2022-49904

Positive Technologies (AI Summary)

CVSS v3.1

5.5

Medium

Base vector

AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H

Name of the Vulnerable Software and Affected Versions Linux kernel (affected versions not specified)

Description A null pointer dereference issue has been identified in the Linux kernel, specifically in the neigh table clear() function. This issue occurs when the IPv6 module is initialized but encounters an error, resulting in a kernel panic. The panic is triggered by a null pointer dereference in the dev net() function when dev is NULL. The estimated number of potentially affected devices worldwide is not available. There is no information about real-world incidents where this issue was exploited.

Technical details about exploitation include:

• The neigh table clear() function is vulnerable.
• The neigh ifdown() function is also affected, specifically when dev is NULL.
• The pneigh queue purge() function is called with dev net(dev == NULL), which triggers the null pointer dereference.
• The dev net() function is used with a NULL dev parameter, causing the issue.

Recommendations To resolve this issue, pass NULL to pneigh queue purge() in neigh ifdown() when dev is NULL, preventing the kernel from panicking immediately. As a temporary workaround, consider disabling the IPv6 module until a patch is available. Restrict access to the neigh table clear() function to minimize the risk of exploitation. Avoid using the dev net() function with a NULL dev parameter until the issue is resolved. At the moment, there is no information about a newer version that contains a fix for this vulnerability.

Exploit

NULL Pointer Dereference

Weakness Enumeration

CWE-476

Related Identifiers

CVE-2022-49904

Affected Products

Astra Linux

Linux Kernel

References · 18

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2022/49xxx/CVE-2022-49904.json · Exploit
• https://osv.dev/vulnerability/CVE-2022-49904 · Vendor Advisory
• https://ubuntu.com/security/CVE-2022-49904 · Vendor Advisory
• https://git.kernel.org/stable/c/a99a8ec4c62180c889482a2ff6465033e0743458 · Patch
• https://security-tracker.debian.org/tracker/CVE-2022-49904 · Vendor Advisory
• https://git.kernel.org/stable/c/0d38b4ca6679e72860ff8730e79bb99d0e9fa3b0 · Patch
• https://git.kernel.org/stable/c/2b45d6d0c41cb9593868e476681efb1aae5078a1 · Patch
• https://cve.org/CVERecord?id=CVE-2022-49904 · Security Note
• https://osv.dev/vulnerability/UBUNTU-CVE-2022-49904 · Vendor Advisory
• https://git.kernel.org/stable/c/1c89642e7f2b7ecc9635610653f5c2f0276c0051 · Patch
• https://git.kernel.org/stable/c/b49f6b2f21f543d4dc88fb7b1ec2adccb822f27c · Patch
• https://git.kernel.org/stable/c/f8017317cb0b279b8ab98b0f3901a2e0ac880dad · Patch
• https://git.kernel.org/stable/c/b736592de2aa53aee2d48d6b129bc0c892007bbe · Patch
• https://osv.dev/vulnerability/DEBIAN-CVE-2022-49904 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2022-49904 · Security Note