An issue has been discovered in GitLab CE/EE affecting all versions before 16.9.7, all versions starting from 16.10 before 16.10.5, all versions starting from 16.11 before 16.11.2. It was possible for an attacker to cause a denial of service using maliciously crafted markdown content.
Weakness
The product uses a regular expression with an inefficient, possibly exponential worst-case computational complexity that consumes excessive CPU cycles.
Affected Software
| Name | Vendor | Start Version | End Version |
|---|---|---|---|
| Gitlab | Gitlab | * | 16.9.7 (excluding) |
| Gitlab | Gitlab | 16.10.0 (including) | 16.10.5 (excluding) |
| Gitlab | Gitlab | 16.11.0 (including) | 16.11.2 (excluding) |
| Gitlab | Ubuntu | esm-apps/xenial | * |
Extended Description
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.