SB20260928299 - Use-after-free in Linux kernel proc_flush_pid() PID handling in kernel/exit.c
Published: September 28, 2026 Updated: September 30, 2026
Security Bulletin ID
SB20260928299
CSH Severity
Low
Patch available
YES
Number of vulnerabilities
1
Exploitation vector
Local access
Highest impact
Code execution
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 1 vulnerability.
1) Use-after-free (CVE-ID: CVE-2026-97903)
CWE-ID: CWE-416 - Use After Free
CVSSv4: 8.5 [CVSS:4.0/AV:L/AC:L/AT:N/PR:L/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a local user to trigger a use-after-free.
The vulnerability exists due to improper reference counting in proc_flush_pid() when racing wait4(-1) against setsid(). A local user can race wait4(-1) against setsid() to trigger a use-after-free.
Remediation
Install update from vendor's website.