A race condition within the Linux kernel entry mechanism allows local attackers to bypass seccomp security filters, posing a significant risk of unauthorized system call execution.

This is a race condition vulnerability occurring during the ptrace stop process in the syscall entry path. An unprivileged local attacker can exploit this flaw when a seccomp filter is updated via TSYNC, causing the kernel to ignore the updated filter and execute restricted system calls.

Successful exploitation of this vulnerability allows a local attacker to execute system calls that should have been blocked by security policies. This could lead to a full compromise of local security boundaries, unauthorized system access, or the execution of privileged operations that could result in total system compromise. Given the CVSS score of 8.4, this is a high-severity issue that requires prompt attention to maintain the integrity of the host operating system.

Immediate Action: Update the Linux kernel to version 6.18.51, 7.2.4, or later to incorporate the necessary synchronization fixes.

Proactive Monitoring: Monitor system logs for unusual ptrace activity or unexpected system call patterns originating from untrusted local user processes.

Compensating Controls: Since this is a local kernel vulnerability, ensure that access to ptrace capabilities is restricted to authorized users via security modules like SELinux or AppArmor.

Public Exploit Available: No (exploit_available unknown)

This kernel vulnerability represents a serious threat to local system security by undermining the effectiveness of seccomp sandboxing. Administrators should prioritize patching the kernel across all impacted environments to eliminate the race condition. Until patches are applied, restrict local user permissions and limit the use of ptrace where possible to reduce the attack surface.