CVE-2026-40217: Remote Code Execution via Sandbox Escape in LiteLLM

Vulnerability ID: CVE-2026-40217

CVSS Score: 8.8

Published: 2026-05-11

LiteLLM, an open-source LLM proxy, contains a critical sandbox escape vulnerability in its guardrail testing endpoint. An authenticated attacker can bypass regex-based source-code filtering by leveraging Python object hierarchy traversal and runtime bytecode manipulation, leading to arbitrary code execution as the process owner.

TL;DR

An authenticated RCE vulnerability exists in LiteLLM's /guardrails/test_custom_code endpoint.…