CVE-2025-53539

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/rennf93/fastapi-guard/commit/d9d50e8130b7b434cdc1b001b8cfd03a06729f7f
https://github.com/rennf93/fastapi-guard/security/advisories/GHSA-j47q-rc62-w448

Configurations

No configuration.

History

08 Jul 2025, 16:18

Type	Values Removed	Values Added
New CVE

Information

Published : 2025-07-07 20:15

Updated : 2025-07-08 16:18

NVD link : CVE-2025-53539

Mitre link : CVE-2025-53539

CVE.ORG link : CVE-2025-53539

JSON object : View

Products Affected

No product.

CWE

CWE-1333

Inefficient Regular Expression Complexity

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