CVE-2025-62426 (GCVE-0-2025-62426)

Vulnerability from cvelistv5 – Published: 2025-11-21 01:21 – Updated: 2025-11-24 18:12
VLAI
Title
vLLM vulnerable to DoS via large Chat Completion or Tokenization requests with specially crafted `chat_template_kwargs`
Summary
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.
Severity
6.5 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2025-11-24 17:12 UTC
CWE
  • CWE-770 - Allocation of Resources Without Limits or Throttling
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7634 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
vllm-project vllm Affected: >= 0.5.5, < 0.11.1
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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