CVE-2025-54365

HIGH

fastapi-guard 3.0.1 - Regular Expression Denial of Service via Script Tag Attribute Bypass

Title source: llm
STIX 2.1

Description

fastapi-guard is a security library for FastAPI that provides middleware to control IPs, log requests, detect penetration attempts and more. In version 3.0.1, the regular expression patched to mitigate the ReDoS vulnerability by limiting the length of string fails to catch inputs that exceed this limit. This type of patch fails to detect cases in which the string representing the attributes of a <script> tag exceeds 100 characters. As a result, most of the regex patterns present in version 3.0.1 can be bypassed. This is fixed in version 3.0.2.

Scores

CVSS v3 7.5
EPSS 0.0070
EPSS Percentile 48.3%
Attack Vector NETWORK
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

CISA SSVC

Vulnrichment
Exploitation poc
Automatable yes
Technical Impact partial

Details

CWE
CWE-1333 CWE-20 CWE-185
Status published
Products (2)
fastapi-guard/fastapi_guard 3.0.1
pypi/fastapi-guard 3.0.1 - 3.0.2PyPI
Published Jul 23, 2025
Tracked Since Feb 18, 2026