procps-ng, procps is vulnerable to a process hiding through race condition. Since the kernel's proc_pid_readdir() returns PID entries in ascending numeric order, a process occupying a high PID can use inotify events to determine when the process list is being scanned, and fork/exec to obtain a lower PID, thus avoiding enumeration. An unprivileged attacker can hide a process from procps-ng's utilities by exploiting a race condition in reading /proc/PID entries. This vulnerability affects procps and procps-ng up to version 3.3.15, newer versions might be affected also.
Severity
CVSS 3.0
5.9 medium
CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
EPSS
4.1% chance of exploitation in the next 30 days; higher than 90% of CVEs (scores of 2026-10-31)