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CVE-2026-115918

Full vulnerability record from the local CVENow database.

Description

vLLM is an inference and serving engine for large language models. From 0.16.0 until 0.32.0, the /v1/responses endpoint allows an authenticated caller to place an attacker-controlled template in chat_template_kwargs[chat_template] when no server template is configured. ChatParams.get_apply_chat_template_kwargs() preserves that value without enforcing trust_request_chat_template, so the request can bypass the intended trust policy and cause CPU or memory exhaustion through Jinja rendering. This issue is fixed in version 0.32.0.

Severity
MEDIUM
CVSS score
6.5 (v3.1)
Vulnerability status
Analyzed
Source identifier
Published
2026-10-26 18:17:39.440000
Last modified
2026-10-30 15:16:46.123000
View original CVE JSON
{
  "id": "CVE-2026-115918",
  "sourceIdentifier": "[email protected]",
  "published": "2026-10-26T18:17:39.440",
  "lastModified": "2026-10-30T15:16:46.123",
  "vulnStatus": "Analyzed",
  "cveTags": [],
  "descriptions": [
    {
      "lang": "en",
      "value": "vLLM is an inference and serving engine for large language models. From 0.16.0 until 0.32.0, the /v1/responses endpoint allows an authenticated caller to place an attacker-controlled template in chat_template_kwargs[chat_template] when no server template is configured. ChatParams.get_apply_chat_template_kwargs() preserves that value without enforcing trust_request_chat_template, so the request can bypass the intended trust policy and cause CPU or memory exhaustion through Jinja rendering. This issue is fixed in version 0.32.0."
    }
  ],
  "affected": [
    {
      "source": "[email protected]",
      "affectedData": [
        {
          "vendor": "vllm-project",
          "product": "vllm",
          "versions": [
            {
              "version": ">= 0.16.0, < 0.32.0",
              "status": "affected"
            }
          ]
        }
      ]
    }
  ],
  "metrics": {
    "cvssMetricV31": [
      {
        "source": "[email protected]",
        "type": "Secondary",
        "cvssData": {
          "version": "3.1",
          "vectorString": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H",
          "baseScore": 6.5,
          "baseSeverity": "MEDIUM",
          "attackVector": "NETWORK",
          "attackComplexity": "LOW",
          "privilegesRequired": "LOW",
          "userInteraction": "NONE",
          "scope": "UNCHANGED",
          "confidentialityImpact": "NONE",
          "integrityImpact": "NONE",
          "availabilityImpact": "HIGH"
        },
        "exploitabilityScore": 2.8,
        "impactScore": 3.6
      }
    ],
    "ssvcV203": [
      {
        "source": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
        "ssvcData": {
          "timestamp": "2026-10-30T14:22:12.561297Z",
          "id": "CVE-2026-115918",
          "options": [
            {
              "exploitation": "none"
            },
            {
              "automatable": "no"
            },
            {
              "technicalImpact": "partial"
            }
          ],
          "role": "CISA Coordinator",
          "version": "2.0.3"
        }
      }
    ]
  },
  "weaknesses": [
    {
      "source": "[email protected]",
      "type": "Secondary",
      "description": [
        {
          "lang": "en",
          "value": "CWE-400"
        },
        {
          "lang": "en",
          "value": "CWE-770"
        }
      ]
    }
  ],
  "configurations": [
    {
      "nodes": [
        {
          "operator": "OR",
          "negate": false,
          "cpeMatch": [
            {
              "vulnerable": true,
              "criteria": "cpe:2.3:a:vllm:vllm:*:*:*:*:*:*:*:*",
              "versionStartIncluding": "0.16.0",
              "versionEndExcluding": "0.32.0",
              "matchCriteriaId": "94B5D4F5-1306-4471-A73A-1AA736CE851D"
            }
          ]
        }
      ]
    }
  ],
  "references": [
    {
      "url": "https://github.com/vllm-project/vllm/commit/cff08b461e086523cee8bba5bd3c66d302625134",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/vllm-project/vllm/pull/50300",
      "source": "[email protected]",
      "tags": [
        "Patch"
      ]
    },
    {
      "url": "https://github.com/vllm-project/vllm/releases/tag/v0.32.0",
      "source": "[email protected]",
      "tags": [
        "Release Notes"
      ]
    },
    {
      "url": "https://github.com/vllm-project/vllm/security/advisories/GHSA-x567-49g5-p4cf",
      "source": "[email protected]",
      "tags": [
        "Patch",
        "Vendor Advisory"
      ]
    }
  ]
}