CVE-2025-59152: Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. In version 2.17.0, rate limits can be completely bypassed by manipulating the X...

Description

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. In version 2.17.0, rate limits can be completely bypassed by manipulating the X-Forwarded-For header. This renders IP-based rate limiting ineffective against determined attackers. Litestar's RateLimitMiddleware uses `cache_key_from_request()` to generate cache keys for rate limiting. When an X-Forwarded-For header is present, the middleware trusts it unconditionally and uses its value as part of the client identifier. Since clients can set arbitrary X-Forwarded-For values, each different spoofed IP creates a separate rate limit bucket. An attacker can rotate through different header values to avoid hitting any single bucket's limit. This affects any Litestar application using RateLimitMiddleware with default settings, which likely includes most applications that implement rate limiting. Version 2.18.0 contains a patch for the vulnerability.

Metrics

CVSS 3.1

7.5/10

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

EPSS Probability

0.44%

35.3th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

CWE-807

References

Timeline

Published: Oct 6, 2025
Last Modified: Jun 17, 2026
Status: Deferred

Frequently Asked Questions

What is CVE-2025-59152?

Litestar is an Asynchronous Server Gateway Interface (ASGI) framework. In version 2.17.0, rate limits can be completely bypassed by manipulating the X-Forwarded-For header. This renders IP-based rate limiting ineffective against determined attackers. Litestar's RateLimitMiddleware uses `cache_key_from_request()` to generate cache keys for rate limiting. When an X-Forwarded-For header is present, the middleware trusts it unconditionally and uses its value as part of the client identifier. Since clients can set arbitrary X-Forwarded-For values, each different spoofed IP creates a separate rate limit bucket. An attacker can rotate through different header values to avoid hitting any single bucket's limit. This affects any Litestar application using RateLimitMiddleware with default settings, which likely includes most applications that implement rate limiting. Version 2.18.0 contains a patch for the vulnerability.

How severe is CVE-2025-59152?

CVE-2025-59152 has a CVSS score of 7.5/10 (HIGH severity). The EPSS model estimates a 0.44% probability of exploitation in the next 30 days.

How do I fix CVE-2025-59152?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.