SB20260815128 - Improper control of a resource through its lifetime in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Improper control of a resource through its lifetime (CVE-ID: CVE-2026-74344)

CWE-ID: CWE-664 - Improper control of a resource through its lifetime

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 improper state management in bpf_rb_root_free() and bpf rbtree node handling when removing a surviving node from a later reused rbtree root allocation. A local user can trigger reuse of a stale bpf rbtree node with retained owner and linkage state to cause a denial of service.

The issue arises when a refcounted object survives being dropped and its rb node retains stale tree linkage and an owner pointer to a freed root.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/2eb39de4962f842d653e96818ae372665cd481fd
• https://git.kernel.org/stable/c/4a7910ee060d8ce55612f5b3cc267f3a265a3cec
• https://git.kernel.org/stable/c/574612793bed416f6c05fe7c9b50e9eb0441997e