{
  "containers": {
    "adp": [
      {
        "metrics": [
          {
            "other": {
              "content": {
                "id": "CVE-2026-73558",
                "options": [
                  {
                    "Exploitation": "poc"
                  },
                  {
                    "Automatable": "no"
                  },
                  {
                    "Technical Impact": "partial"
                  }
                ],
                "role": "CISA Coordinator",
                "timestamp": "2026-08-13T15:38:18.767062Z",
                "version": "2.0.3"
              },
              "type": "ssvc"
            }
          }
        ],
        "providerMetadata": {
          "dateUpdated": "2026-08-13T15:38:40.181Z",
          "orgId": "134c704f-9b21-4f2e-91b3-4a467353bcc0",
          "shortName": "CISA-ADP"
        },
        "references": [
          {
            "tags": [
              "exploit"
            ],
            "url": "https://github.com/vllm-project/vllm/security/advisories/GHSA-7m6h-x95x-82q5"
          }
        ],
        "title": "CISA ADP Vulnrichment"
      }
    ],
    "cna": {
      "affected": [
        {
          "product": "vllm",
          "vendor": "vllm-project",
          "versions": [
            {
              "status": "affected",
              "version": "\u003c 0.27.0"
            }
          ]
        }
      ],
      "descriptions": [
        {
          "lang": "en",
          "value": "vLLM is an inference and serving engine for large language models. Prior to 0.27.0, an integer overflow in blockIdx.x * 2 * d in activation_kernels.cu can cause act_and_mul_kernel to consume another batched user\u0027s input, allowing a request processed in the same inference batch to receive a partial or complete copy of another user\u0027s inference result. This issue is fixed in version 0.27.0."
        }
      ],
      "metrics": [
        {
          "cvssV3_1": {
            "attackComplexity": "HIGH",
            "attackVector": "NETWORK",
            "availabilityImpact": "NONE",
            "baseScore": 5.3,
            "baseSeverity": "MEDIUM",
            "confidentialityImpact": "HIGH",
            "integrityImpact": "NONE",
            "privilegesRequired": "NONE",
            "scope": "UNCHANGED",
            "userInteraction": "REQUIRED",
            "vectorString": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N",
            "version": "3.1"
          }
        }
      ],
      "problemTypes": [
        {
          "descriptions": [
            {
              "cweId": "CWE-190",
              "description": "CWE-190: Integer Overflow or Wraparound",
              "lang": "en",
              "type": "CWE"
            }
          ]
        }
      ],
      "providerMetadata": {
        "dateUpdated": "2026-08-13T15:06:06.584Z",
        "orgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
        "shortName": "GitHub_M"
      },
      "references": [
        {
          "name": "https://github.com/vllm-project/vllm/security/advisories/GHSA-7m6h-x95x-82q5",
          "tags": [
            "x_refsource_CONFIRM"
          ],
          "url": "https://github.com/vllm-project/vllm/security/advisories/GHSA-7m6h-x95x-82q5"
        },
        {
          "name": "https://github.com/vllm-project/vllm/issues/42860",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vllm-project/vllm/issues/42860"
        },
        {
          "name": "https://github.com/vllm-project/vllm/pull/49660",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vllm-project/vllm/pull/49660"
        },
        {
          "name": "https://github.com/vllm-project/vllm/commit/451227cb3ff07989698fed982c2d3e4300257924",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vllm-project/vllm/commit/451227cb3ff07989698fed982c2d3e4300257924"
        },
        {
          "name": "https://github.com/vllm-project/vllm/releases/tag/v0.27.0",
          "tags": [
            "x_refsource_MISC"
          ],
          "url": "https://github.com/vllm-project/vllm/releases/tag/v0.27.0"
        }
      ],
      "source": {
        "advisory": "GHSA-7m6h-x95x-82q5",
        "discovery": "UNKNOWN"
      },
      "title": "vLLM: Cross-User Data Leak Vulnerability"
    }
  },
  "cveMetadata": {
    "assignerOrgId": "a0819718-46f1-4df5-94e2-005712e83aaa",
    "assignerShortName": "GitHub_M",
    "cveId": "CVE-2026-73558",
    "datePublished": "2026-08-13T15:06:06.584Z",
    "dateReserved": "2026-08-12T20:53:46.380Z",
    "dateUpdated": "2026-08-13T15:38:40.181Z",
    "state": "PUBLISHED"
  },
  "dataType": "CVE_RECORD",
  "dataVersion": "5.2"
}

{
  "affected": [
    {
      "package": {
        "ecosystem": "PyPI",
        "name": "vllm"
      },
      "ranges": [
        {
          "events": [
            {
              "introduced": "0"
            },
            {
              "fixed": "0.27.0"
            }
          ],
          "type": "ECOSYSTEM"
        }
      ]
    }
  ],
  "aliases": [
    "CVE-2026-73558"
  ],
  "database_specific": {
    "cwe_ids": [
      "CWE-190"
    ],
    "github_reviewed": true,
    "github_reviewed_at": "2026-09-08T20:24:49Z",
    "nvd_published_at": "2026-08-13T15:20:18Z",
    "severity": "MODERATE"
  },
  "details": "### Summary\nAn integer overflow in the act_and_mul_kernel kernel can cause the output of one user request to be incorporated into the response of another request within the same inference batch. Under certain conditions, the last request in a batch can receive a partial or complete copy of the first user\u0027s inference result, resulting in cross-user data leakage.\n\n\n### Details\nThe root cause is an integer overflow in the expression blockIdx.x * 2 * d at https://github.com/vllm-project/vllm/blob/ff712f6447093d07747c88680b9d006b119f5890/csrc/activation_kernels.cu#L82. \n\nAs a result, the computation for one user (User A) can incorrectly consume input data from another user (User B). In particular, when 2^32 is divisible by d, the overflow can cause User A\u0027s output to contain portions of User B\u0027s inference result. In some cases, User B\u0027s response may be copied entirely into User A\u0027s response.\n\nThis constitutes a severe cross-user information disclosure vulnerability and is straightforward to trigger.\n### PoC\nWe reproduced the issue using meta-llama/Llama-3.2-1B-Instruct, for which d = 8192.\n\nUsing the following configuration:\n\nBatch size: 17\nSequence length: 16384\n\nThe final response in the batch becomes an exact copy of the first response in the batch, demonstrating complete cross-user data leakage.\n\n### Impact\nThis vulnerability enables cross-user information disclosure. An attacker can intentionally craft requests that are processed within the same inference batch as a victim\u0027s request and cause the victim\u0027s inference output to be copied into the attacker\u0027s response.\n\nAs a result, sensitive information contained in another user\u0027s model response may be exposed to an unauthorized party.\n\n### Versions\n\nFor versions prior and equal to 0.21.0, the bug is in csrc/activation_kernels.cu, and for versions later than 0.21.0, the bug is in csrc/libtorch_stable/activation_kernels.cu.",
  "id": "GHSA-7m6h-x95x-82q5",
  "modified": "2026-09-08T20:24:49Z",
  "published": "2026-09-08T20:24:49Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/security/advisories/GHSA-7m6h-x95x-82q5"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-73558"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/issues/42860"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/pull/49660"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/commit/451227cb3ff07989698fed982c2d3e4300257924"
    },
    {
      "type": "PACKAGE",
      "url": "https://github.com/vllm-project/vllm"
    },
    {
      "type": "WEB",
      "url": "https://github.com/vllm-project/vllm/releases/tag/v0.27.0"
    }
  ],
  "schema_version": "1.4.0",
  "severity": [
    {
      "score": "CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:N/A:N",
      "type": "CVSS_V3"
    }
  ],
  "summary": "vLLM: Cross-User Data Leak Vulnerability"
}