CVE-2021-39938
Description
A vulnerable regular expression pattern in GitLab CE/EE since version 8.15 before 14.3.6, all versions starting from 14.4 before 14.4.4, all versions starting from 14.5 before 14.5.2, allows an attacker to cause uncontrolled resource consumption leading to Denial of Service via specially crafted deploy Slash commands
Summary dbcve.org
ReDoS (Regular Expression Denial of Service) vulnerability in GitLab's deploy Slash command processing. A specially crafted regex pattern in the slash command parser allows attacker-controlled input to cause catastrophic backtracking, consuming excessive CPU and memory leading to service unavailability.
Mitigation
Upgrade GitLab to version 14.3.6, 14.4.4, 14.5.2 or later. As a compensating control, implement input validation and length limits on slash command parameters until patching is completed.