Improper input validation in Fastapi-Guard Fastapi Guard
CVE-2025-54365
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.
Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)
EPSS: 0.007 (50.7th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Fastapi-guard Fastapi_guard — versions 3.0.1
- Rennf93 Fastapi-guard — versions >= 3.0.1, < 3.0.2
Weakness classification (CWE)
Public proof-of-concept exploits
References
- security-advisories@github.com (x_refsource_CONFIRM, Exploit, Vendor Advisory)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Patch, x_refsource_MISC)
Frequently asked questions
- What is CVE-2025-54365?
- CVE-2025-54365 is a high-severity vulnerability in Fastapi-Guard Fastapi Guard, classified under Improper Input Validation. CVSS score: 7.5/10. Published 2025-07-23.
- How severe is CVE-2025-54365?
- High severity. CVSS v3 base score is 7.5 out of 10.
- Is CVE-2025-54365 known to be exploited?
- 1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.