LMCache through 0.5.5 contains an unauthenticated remote code execution vulnerability that allows remote attackers to execute Python code by posting scripts to the /runscript endpoint. Attackers can recover real builtins through the injected FastAPI app object, bypassing the guarded import, to import os and run operating system commands as the LMCache process.

A flaw has been found in LMCache up to 0.4.6. This affects the function hexhashtoint16 of the file lmcache/integration/vllm/utils.py of the component KV Cache Handler. Executing a manipulation can lead to use of weak hash. The attack needs to be launched locally. The attack requires a high level of complexity. It is indicated that the exploitability is difficult. The exploit has been published and may be used. The pull request to fix this issue awaits acceptance.