Vulnerability-Lookup

GHSA-G3CP-V4CP-9XFQ

Vulnerability from github – Published: 2026-09-22 00:30 – Updated: 2026-09-22 00:30

Details

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

7.5 (High)


                  
                    CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

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

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{
  "affected": [],
  "aliases": [
    "CVE-2026-94623"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-617"
    ],
    "github_reviewed": false,
    "github_reviewed_at": null,
    "nvd_published_at": "2026-09-21T22:17:01Z",
    "severity": "HIGH"
  },
  "details": "vLLM through 0.29.0 contains a denial of service vulnerability in the NIXL connector\u0027s 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.",
  "id": "GHSA-g3cp-v4cp-9xfq",
  "modified": "2026-09-22T00:30:55Z",
  "published": "2026-09-22T00:30:55Z",
  "references": [
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-94623"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/pull/51505"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/blob/v0.29.0/vllm/distributed/kv_transfer/kv_connector/v1/nixl/base_worker.py#L2642-L2646"
    },
    {
      "type": "WEB",
      "url": "https://www.vulncheck.com/advisories/vllm-through-0.29.0-denial-of-service-via-nixl-multi-prompt-assertion-failure"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H",
      "type": "CVSS_V3"
    },
    {
      "score": "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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X",
      "type": "CVSS_V4"
    }
  ]
}

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

Vulnerability from cvelistv5 – Published: 2026-09-21 22:04 – Updated: 2026-09-22 17:44

Title

vLLM through 0.29.0 Denial of Service via NIXL Multi-Prompt Assertion Failure

Summary

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

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

VulnCheck mitre root

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
vllm-project	vllm	Affected: 0 , ≤ 0.29.0 (semver) cpe:2.3:a:vllm:vllm::::::::

Date Public

2026-08-08 00:00

Credits

Mingkai Yu Jiapeng Li Jiajia Liu

Show details on NVD website

JSON

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  "containers": {
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        "metrics": [
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            "other": {
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                "id": "CVE-2026-94623",
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                  },
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                  },
                  {
                    "Technical Impact": "partial"
                  }
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                "role": "CISA Coordinator",
                "timestamp": "2026-09-22T17:19:44.934826Z",
                "version": "2.0.3"
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Sightings

Author	Source	Type	Date	Other

Nomenclature

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Confirmed: The vulnerability has been validated from an analyst's perspective.
Published Proof of Concept: A public proof of concept is available for this vulnerability.
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Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
Not confirmed: The user expressed doubt about the validity of the vulnerability.
Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.

The MITRE ATT&CK techniques below are AI-generated suggestions, inferred from the description of the vulnerability by the CIRCL/vulnerability-attack-technique-classification-roberta-base model, served locally by ML-Gateway. They have not been verified by an analyst and are provided for guidance only.
The approach is described in our paper Mapping CVEs to MITRE ATT&CK Techniques: A Curated Gold-Set Classifier and the Limits of LLM-Assisted Label Expansion.
Browse all ATT&CK techniques and the vulnerabilities related to each.

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GHSA-G3CP-V4CP-9XFQ

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

Tags

Sightings

Nomenclature

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