CVE-2025-59152 is a high-severity (CVSS 7.5) CWE-807 vulnerability in litestar. O3 Security confirms whether CVE-2025-59152 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
X-Forwarded-For Header Spoofing Bypasses Litestar Rate Limiting
Real-World Exposure
litestarReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | litestar | ≥ 2.17.0&&< 2.18.0 | 2.18.0 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for litestar. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update litestar to 2.18.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-59152 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 pinpoints whether CVE-2025-59152 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2025-59152. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2025-59152 in your dependencies?
O3 detects CVE-2025-59152 across PyPI dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.