CVE-2026-94627 (GCVE-0-2026-94627)

Vulnerability from cvelistv5 – Published: 2026-09-21 22:04 – Updated: 2026-09-21 22:04
VLAI
Title
vLLM through 0.29.0 GPU KV Cache Leak via Mooncake Transfer ID Collision
Summary
vLLM Mooncake connector through 0.29.0 fails to properly manage GPU KV cache block ownership when concurrent child requests share a single transfer ID in prefill/decode disaggregated deployments. Attackers can trigger GPU memory exhaustion by submitting completion requests with multiple prompts, causing orphaned KV cache blocks to accumulate until process restart and eventually preventing legitimate requests from executing.
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
  • CWE-401 - Missing Release of Memory after Effective Lifetime
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
2026-07-25 00:00
Credits
Mingkai Yu Jiapeng Li Jiajia Liu
Show details on NVD website
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{
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          "vendor": "vllm-project",
          "versions": [
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              "status": "affected",
              "version": "0",
              "versionType": "semver"
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        }
      ],
      "metrics": [
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            "attackRequirements": "NONE",
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            "userInteraction": "NONE",
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            "version": "3.1"
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          "descriptions": [
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              "description": "Missing Release of Memory after Effective Lifetime",
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      "providerMetadata": {
        "dateUpdated": "2026-09-21T22:04:16.559Z",
        "orgId": "83251b91-4cc7-4094-a5c7-464a1b83ea10",
        "shortName": "VulnCheck"
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      "references": [
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          "name": "Pull Request #49796",
          "tags": [
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            "patch"
          ],
          "url": "https://github.com/vllm-project/vllm/pull/49796"
        },
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          "tags": [
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          "url": "https://github.com/vllm-project/vllm/blob/v0.29.0/vllm/distributed/kv_transfer/kv_connector/v1/mooncake/mooncake_connector.py#L1978-L1989"
        },
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          "url": "https://github.com/vllm-project/vllm"
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          "url": "https://www.vulncheck.com/advisories/vllm-through-0.29.0-gpu-kv-cache-leak-via-mooncake-transfer-id-collision"
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      "title": "vLLM through 0.29.0 GPU KV Cache Leak via Mooncake Transfer ID Collision",
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  "cveMetadata": {
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    "assignerShortName": "VulnCheck",
    "cveId": "CVE-2026-94627",
    "datePublished": "2026-09-21T22:04:16.559Z",
    "dateReserved": "2026-09-21T21:42:30.080Z",
    "dateUpdated": "2026-09-21T22:04:16.559Z",
    "state": "PUBLISHED"
  },
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  "dataVersion": "5.2",
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        "cveTags": [],
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          }
        ],
        "id": "CVE-2026-94627",
        "lastModified": "2026-09-21T22:17:01.740",
        "metrics": {
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                "userInteraction": "NONE",
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          "cvssMetricV40": [
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                "Recovery": "NOT_DEFINED",
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                "availabilityRequirement": "NOT_DEFINED",
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                "exploitMaturity": "NOT_DEFINED",
                "integrityRequirement": "NOT_DEFINED",
                "modifiedAttackComplexity": "NOT_DEFINED",
                "modifiedAttackRequirements": "NOT_DEFINED",
                "modifiedAttackVector": "NOT_DEFINED",
                "modifiedPrivilegesRequired": "NOT_DEFINED",
                "modifiedSubAvailabilityImpact": "NOT_DEFINED",
                "modifiedSubConfidentialityImpact": "NOT_DEFINED",
                "modifiedSubIntegrityImpact": "NOT_DEFINED",
                "modifiedUserInteraction": "NOT_DEFINED",
                "modifiedVulnAvailabilityImpact": "NOT_DEFINED",
                "modifiedVulnConfidentialityImpact": "NOT_DEFINED",
                "modifiedVulnIntegrityImpact": "NOT_DEFINED",
                "privilegesRequired": "NONE",
                "providerUrgency": "NOT_DEFINED",
                "subAvailabilityImpact": "NONE",
                "subConfidentialityImpact": "NONE",
                "subIntegrityImpact": "NONE",
                "userInteraction": "NONE",
                "valueDensity": "NOT_DEFINED",
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            "source": "disclosure@vulncheck.com",
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}



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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

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Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • 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.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • 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.


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