CVE-2026-94623 (GCVE-0-2026-94623)
Vulnerability from cvelistv5 – Published: 2026-09-21 22:04 – Updated: 2026-09-22 17:44
VLAI
EPSS
VEX
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
SSVC
Exploitation: none
Automatable: yes
Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-22 17:19 UTC
CWE
- CWE-617 - Reachable Assertion
Assigner
References
4 references
| URL | Tags |
|---|---|
| https://github.com/vllm-project/vllm/pull/51505 | issue-trackingpatch |
| https://github.com/vllm-project/vllm/blob/v0.29.0… | technical-description |
| https://github.com/vllm-project/vllm | product |
| https://www.vulncheck.com/advisories/vllm-through… | third-party-advisory |
Impacted products
1 product
| Vendor | Product | Version | CPE status | |
|---|---|---|---|---|
| vllm-project | vllm |
Affected:
0 , ≤ 0.29.0
(semver)
cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:* |
Date Public
2026-08-08 00:00
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