An issue has been discovered in GitLab CE/EE affecting all versions starting from 12.3 before 16.3.6, all versions starting from 16.4 before 16.4.2, all versions starting from 16.5 before 16.5.1. A Regular Expression Denial of Service was possible by adding a large string in timeout input in gitlab-ci.yml file.
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Gitlab | Gitlab | 12.3.0 (including) | 16.3.6 (excluding) |
| Gitlab | Gitlab | 16.4.0 (including) | 16.4.2 (excluding) |
| Gitlab | Gitlab | 16.5.0 (including) | 16.5.0 (including) |
| Gitlab | Ubuntu | esm-apps/xenial | * |
Attackers can create crafted inputs that
intentionally cause the regular expression to use
excessive backtracking in a way that causes the CPU
consumption to spike.