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vLLMGHSA-wr9h-g72x-mwhm

vLLM is vulnerable to timing attack at bearer auth

High7.5CVE-2025-59425 · Published Oct 7, 2025 · updated Sep 10, 2026

GitHub advisory

Affected versions

PackageAffectedFixed in
vllm
PyPI
< 0.11.00.11.0
Details and references

### Summary The API key support in vLLM performed validation using a method that was vulnerable to a timing attack. This could potentially allow an attacker to discover a valid API key using an approach more efficient than brute force. ### Details https://github.com/vllm-project/vllm/blob/4b946d693e0af15740e9ca9c0e059d5f333b1083/vllm/entrypoints/openai/api_server.py#L1270-L1274 API key validation used a string comparison that will take longer the more characters the provided API key gets correct. Data analysis across many attempts can allow an attacker to determine when it finds the next correct character in the key sequence. ### Impact Deployments relying on vLLM's built-in API key validation are vulnerable to authentication bypass using this technique.

CVSS 3.1
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Severity from
GitHub (reviewed advisory)
Weakness
CWE-385
Also known as
CVE-2025-59425, PYSEC-2026-2026

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