CVE-2026-90878: vLLM resource consumption through chat_template in /v1/chat/completions

Summary

A vulnerability in vllm-project vLLM up to 0.27.1 affects an unspecified part of the /v1/chat/completions endpoint, in the Jinja Template Rendering component. Manipulating the chat_template argument causes resource consumption, and the attack can be launched remotely. The exploit is publicly disclosed and may be used.

Mitigation

A pull request to fix this issue is awaiting acceptance. No fixed version is stated in the source.

Topics

• Inference infrastructure

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