procps-ng, procps is vulnerable to a process hiding through race condition. Since the kernel's procpidreaddir() 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.

procps-ng procps is vulnerable to a denial of service, caused by a heap based buffer overflow when running the “ps” utility. By sending a specially crafted request, a local authenticated attacker could exploit this vulnerability to cause a denial of service condition.