Vulnerability · Published May 6, 2025 · Assigned by GitHub_M
CVE-2025-46814FastAPI Guard Remote Header Injection via X-Forwarded-For Manipulation
Low 3.4
In plain English
A low-severity injection in fastapi-guard from rennf93. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 28% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.
Official description
FastAPI Guard is a security library for FastAPI that provides middleware to control IPs, log requests, and detect penetration attempts. An HTTP header injection vulnerability has been identified in versions prior to 2.0.0. By manipulating the X-Forwarded-For header, an attacker can potentially inject arbitrary IP addresses into the request. This vulnerability can allow attackers to bypass IP-based access controls, mislead logging systems, and impersonate trusted clients. It is especially impactful when the application relies on the X-Forwarded-For header for IP-based authorization or authentication. Users should upgrade to FastAPI Guard version 2.0.0 to receive a fix.
Affected packages & fixed versions
| Ecosystem | Package | Fixed in | Advisory |
|---|---|---|---|
| PyPI | fastapi-guard | 2.0.0 | PYSEC-2025-242 |
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| rennf93 | fastapi-guard | < 2.0.0 |
Weakness: CWE-74 · Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:C/C:L/I:N/A:N