SB20260720309 - Use-after-free in Linux kernel xfrm
Published: July 20, 2026
Security Bulletin ID
SB20260720309
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Denial of service
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-63919)
CWE-ID: CWE-416 - Use After Free
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 user to cause a denial of service.
The vulnerability exists due to a use-after-free in xfrm transport-mode deferred reinjection handling in net/xfrm/xfrm_input.c when processing deferred transport reinjection callbacks that use a stored network namespace pointer. A local user can trigger deferred transport reinjection with a dangling net namespace reference to cause a denial of service.
Remediation
Install update from vendor's website.
References
- https://git.kernel.org/stable/c/2df7059a18afb7d3aee6c36cad5d371c198111d4
- https://git.kernel.org/stable/c/48ce101cd630d6745b6923b5bad8358bc4c119da
- https://git.kernel.org/stable/c/55ddfc41451f01c588089cd74957a05311b6f202
- https://git.kernel.org/stable/c/7ee59eda8820b758ed29e1cd3222359c7b97302c
- https://git.kernel.org/stable/c/8dfabcba6a943a7a02ebe1e1637c361ba96acbaa
- https://git.kernel.org/stable/c/9f67a36e91bb50d358760f381f233913fe5c09f8
- https://git.kernel.org/stable/c/9f7ebb45a83afc3216e855e57d51bb4bc9b5232e
- https://git.kernel.org/stable/c/c16f74dc1d75d0e2e7670076d5375deda110ebeb