Bug 2416278 (CVE-2025-62426) - CVE-2025-62426 vllm: vLLM vulnerable to DoS via large Chat Completion or Tokenization requests with specially crafted `chat_template_kwargs`
Summary: CVE-2025-62426 vllm: vLLM vulnerable to DoS via large Chat Completion or Toke...
Keywords:
Status: NEW
Alias: CVE-2025-62426
Product: Security Response
Classification: Other
Component: vulnerability
Version: unspecified
Hardware: All
OS: Linux
medium
medium
Target Milestone: ---
Assignee: Product Security DevOps Team
QA Contact:
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Depends On:
Blocks:
TreeView+ depends on / blocked
 
Reported: 2025-11-21 02:01 UTC by OSIDB Bzimport
Modified: 2025-11-25 07:06 UTC (History)
7 users (show)

Fixed In Version:
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Description OSIDB Bzimport 2025-11-21 02:01:13 UTC 
vLLM is an inference and serving engine for large language models (LLMs). From version 0.5.5 to before 0.11.1, the /v1/chat/completions and /tokenize endpoints allow a chat_template_kwargs request parameter that is used in the code before it is properly validated against the chat template. With the right chat_template_kwargs parameters, it is possible to block processing of the API server for long periods of time, delaying all other requests. This issue has been patched in version 0.11.1.
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