An input validation issue in the asset proxy in GitLab EE, affecting all versions from 12.3 prior to 16.2.8, 16.3 prior to 16.3.5, and 16.4 prior to 16.4.1, allowed an authenticated attacker to craft image urls which bypass the asset proxy.
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 (including) | 16.2.8 (excluding) |
| Gitlab | Gitlab | 16.3.0 (including) | 16.3.5 (excluding) |
| Gitlab | Gitlab | 16.4.0 (including) | 16.4.0 (including) |
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.