CVE-2026-94623 (GCVE-0-2026-94623)

Vulnerability from cvelistv5 – Published: 2026-09-21 22:04 – Updated: 2026-09-21 22:04
VLAI
Title
vLLM through 0.29.0 Denial of Service via NIXL Multi-Prompt Assertion Failure
Summary
vLLM through 0.29.0 contains a denial of service vulnerability in the NIXL connector's prefix caching implementation that fails to properly validate block counts across multi-prompt completion requests in prefill/decode disaggregated deployments. Attackers can trigger an assertion failure in NixlBaseConnectorWorker._apply_prefix_caching by submitting completion requests with multiple prompts of varying lengths, causing the decode worker to terminate and become unavailable until restarted.
Severity
8.7 (High)
CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE
Assigner
References
Impacted products
Vendor Product Version CPE status
vllm-project vllm Affected: 0 , ≤ 0.29.0 (semver)
    cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*
Create a notification for this product.
Date Public
2026-08-08 00:00
Credits
Mingkai Yu Jiapeng Li Jiajia Liu
Show details on NVD website
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}



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  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
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  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.



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