Internal Syscall Unix
Monthly
Time-of-check-time-of-use (TOCTOU) race condition in Go's internal/syscall/unix Root.Chmod allows local privileged attackers to modify file permissions on targets outside the intended root filesystem boundary. By replacing the target with a symlink between the permission check and the actual chmod operation, attackers can exploit the Linux fchmodat syscall's behavior of silently ignoring AT_SYMLINK_NOFOLLOW to modify arbitrary files outside the restricted root. Exploitation requires high privileges and precise timing; EPSS score of 0.01% indicates minimal real-world exploitation probability despite moderate CVSS severity.
Time-of-check-time-of-use (TOCTOU) race condition in Go's internal/syscall/unix Root.Chmod allows local privileged attackers to modify file permissions on targets outside the intended root filesystem boundary. By replacing the target with a symlink between the permission check and the actual chmod operation, attackers can exploit the Linux fchmodat syscall's behavior of silently ignoring AT_SYMLINK_NOFOLLOW to modify arbitrary files outside the restricted root. Exploitation requires high privileges and precise timing; EPSS score of 0.01% indicates minimal real-world exploitation probability despite moderate CVSS severity.