SB20261022413 - Use-after-free in Linux kernel bpf

Description

This security bulletin contains information about 1 vulnerability.

1) Use-after-free (CVE-ID: CVE-2026-98800)

CWE-ID: CWE-416 - Use After Free

CVSSv4: 5.6 [CVSS:4.0/AV:L/AC:L/AT:P/PR:H/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N]

The vulnerability allows a local privileged user to cause a denial of service through invalid kernel memory access.

The vulnerability exists due to use-after-free in the Linux kernel BPF trampoline program lifecycle when a detached program is freed while a task on a preemptible kernel is paused in the trampoline before acquiring the program's RCU read lock. A local privileged user can trigger concurrent program detachment and trampoline execution to cause a denial of service when the paused task resumes and accesses the freed program.

Remediation

Install update from vendor's website.

References

• https://git.kernel.org/stable/c/0fb5751a6e411b1b466c06e50021818d9391df98
• https://git.kernel.org/stable/c/40955f6512a03f0e046f5256b0706b26ba191018