CVE-2025-54365
HIGHfastapi-guard 3.0.1 - Regular Expression Denial of Service via Script Tag Attribute Bypass
Title source: llmDescription
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.
References (3)
Core 3
Core References
Exploit, Vendor Advisory x_refsource_confirm
https://github.com/rennf93/fastapi-guard/security/advisories/GHSA-rrf6-pxg8-684g
Patch x_refsource_misc
https://github.com/rennf93/fastapi-guard/commit/0829292c322d33dc14ab00c5451c5c138148035a
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