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CVE-2025-53539
Good to know:
Date: July 7, 2025
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.
Severity Score
Related Resources (5)
Severity Score
Weakness Type (CWE)
Inefficient Regular Expression Complexity
CWE-1333Top Fix
CVSS v3.1
| Base Score: |
|
|---|---|
| Attack Vector (AV): | NETWORK |
| Attack Complexity (AC): | LOW |
| Privileges Required (PR): | NONE |
| User Interaction (UI): | NONE |
| Scope (S): | UNCHANGED |
| Confidentiality (C): | NONE |
| Integrity (I): | NONE |
| Availability (A): | LOW |