Resource exhaustion in Vllm
CVE-2025-62426
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.
EPSS: 0.004 (28.3th percentile) — read the EPSS interpretation.
CVSS v3 metric
CVSS v3 base score 6.5 (Medium). Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H.
Affected products
- Vllm — versions 0.11.1
- Vllm-project Vllm — versions >= 0.5.5, < 0.11.1
Weakness classification (CWE)
References
- security-advisories@github.com (x_refsource_CONFIRM, Vendor Advisory)
- security-advisories@github.com (x_refsource_MISC, Issue Tracking)
- security-advisories@github.com (Patch, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC)
- security-advisories@github.com (Product, x_refsource_MISC)
Frequently asked questions
- What is CVE-2025-62426?
- CVE-2025-62426 is a medium-severity vulnerability in Vllm, classified under Allocation of Resources Without Limits or Throttling. CVSS score: 6.5/10. Published 2025-11-21.
- How severe is CVE-2025-62426?
- Medium severity. CVSS v3 base score is 6.5 out of 10.