SB20260815221 - NULL pointer dereference in Linux kernel ipv6
Published: August 15, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) NULL pointer dereference (CVE-ID: CVE-2026-72502)
CWE-ID: CWE-476 - NULL Pointer Dereference
CVSSv4: 6.8 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local attacker to cause a denial of service.
The vulnerability exists due to a null pointer dereference in skb_segment() when processing a local TCP packet with gso_size set to 0xFFFF. A local attacker can trigger a large MTU condition that causes the MSS clamp to reach 65535 to cause a denial of service.
The issue occurs because the 0xFFFF MSS value collides with the GSO_BY_FRAGS magic value, and local TCP packets do not use frag_list.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/21f69ac1879bb970588d5e7c12a96e6542f7c1a7
- https://git.kernel.org/stable/c/2bf43d0e2e6a27d52a7d624e2d6b9116972e8a22
- https://git.kernel.org/stable/c/560b33b434e922ef97f9ff23aa2e909ef7aacd5c
- https://git.kernel.org/stable/c/572fff10819dfc359298d1f774839e76a4d96f93
- https://git.kernel.org/stable/c/8e6214a530c03e341dc1b0a846c8f2b716b3551a
- https://git.kernel.org/stable/c/a210791f33345aa87187f7d7a9f3b9b7f4a28e6d
- https://git.kernel.org/stable/c/c0db3dc2ac323b6c4b76adede3b355a9daa6dea8
- https://git.kernel.org/stable/c/d774cdbda6634a78d0f2baf201ee5a8c57f3bc0e