CVE-2026-41523

vLLM prior to 0.22.0 is affected by an assert-based security check in the activation function loading that can permit arbitrary code execution when a malicious HuggingFace model is loaded and vLLM runs in Python optimized mode. The attacker-controlled inputs are the activation function names from...

vLLM: Security Check Bypass via assert Statement in Activation Function Loading Allows Arbitrary Code Execution

Summary An assert-based security check in vLLM's activation function loading allows any unauthenticated attacker to achieve arbitrary code execution on the server by publishing a malicious HuggingFace model, when vLLM runs in Python optimized mode python -O or PYTHONOPTIMIZE=1. Details vLLM uses ...

PT-2026-50140

Name of the Vulnerable Software and Affected Versions vLLM versions prior to 0.22.0 Description An assert-based security check in the activation function loading process allows an unauthenticated attacker to achieve arbitrary code execution on the server. This occurs when vLLM is run in Python...