CVE-2026-42203: LiteLLM Server-Side Template Injection

# CVE-2026-42203: LiteLLM Server-Side Template Injection

https://gcdradar.vercel.app/incidents/cve-2026-42203-litellm-server-side-template-injection · AIR-2026-0597 · closed 2026-04-24

- Lane: Patch now
- Severity: 2 (Disclosed vulnerability)
- Fix status: Fix status unknown
- First reported: 2026-04-24
- AI role: Attack on AI
- Products: LiteLLM
- CVE ids: CVE-2026-42203
- CVSS: 8.6

## Summary

LiteLLM Proxy contained a server-side template injection vulnerability in the prompts test endpoint. Authenticated users could run arbitrary code and expose environment secrets.

## What to do

No action recorded; read the sources below and the vendor's advisory.

## Latest updates

- 2026-05-08: CVE-2026-42203: LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. (https://nvd.nist.gov/vuln/detail/CVE-2026-42203)
- 2026-04-24: CVE-2026-42203: LiteLLM: Server-Side Template Injection in /prompts/test endpoint (https://github.com/advisories/GHSA-xqmj-j6mv-4862)

## Sources

- 2026-04-24 GitHub Advisory Database: CVE-2026-42203: LiteLLM: Server-Side Template Injection in /prompts/test endpoint https://github.com/advisories/GHSA-xqmj-j6mv-4862
- 2026-05-08 NVD: CVE-2026-42203: LiteLLM is a proxy server (AI Gateway) to call LLM APIs in OpenAI (or native) format. https://nvd.nist.gov/vuln/detail/CVE-2026-42203

Verify against the vendor's advisory before changing production. Data CC BY-SA 4.0, https://gcdradar.vercel.app.