VULNERABILITY INTELLIGENCE

CVE-2025-53539

CVSS score7.5 HIGH
EPSS probability0.48%
CISA KEVNot currently listed
Published2025-07-07
Last modified2026-06-17
CVSS vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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.

Weakness classification

  • security-advisories@github.com: CWE-1333

Primary references