CVE-2025-53539
ReDoS in fastapi-guard's penetration attempts detector
- State
- Published
- Severity
- 6.9 Medium
- Published
- Jul 7, 2025
- Updated
- Jul 7, 2025
- Reserved
- Jul 2, 2025
Description
FastAPI Guard is a security library for FastAPI that provides middleware to control IPs, log requests, and detect penetration attempts. fastapi-guard's penetration attempts detection uses regex to scan incoming requests. However, some of the regex patterns used in detection are extremely inefficient and can cause polynomial complexity backtracks when handling specially crafted inputs. This vulnerability is fixed in 3.0.1.
Scores
| CVSS | Score | Vector | Source |
|---|---|---|---|
| 4.0 | 6.9 Medium | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N | GitHub_M |
Weaknesses
- CWE-1333 Inefficient Regular Expression Complexity
Affected Products
| Product | Versions |
|---|---|
fastapi-guardrennf93 |
|
References
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