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CVE PROGRAM SOURCE RECORD2.6 Low

CVE-2025-46570

vLLM’s Chunk-Based Prefix Caching Vulnerable to Potential Timing Side-Channel

Description

vLLM is an inference and serving engine for large language models (LLMs). Prior to version 0.9.0, when a new prompt is processed, if the PageAttention mechanism finds a matching prefix chunk, the prefill process speeds up, which is reflected in the TTFT (Time to First Token). These timing differences caused by matching chunks are significant enough to be recognized and exploited. This issue has been patched in version 0.9.0.

Affected products

Version statuses are supplied by the assigning organization. Consult the original record for detailed ranges and platform conditions.

vllm-project vllm

  • < 0.9.0affected

References