Cross-tenant database retargeting via dot/NUL injection in namespace strings in the C Driver

{
  "id": "ed2096008967d9e7d2ed1ce79a98100cef607f558feddcf99e9f0a44afb14915",
  "url": "https://osv.dev/vulnerability/CVE-2026-81524",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "Cross-tenant database retargeting via dot/NUL injection in namespace strings in the C Driver",
    "summary": "A weakness in the MongoDB C Driver allows special elements in caller-supplied database and collection name components to pass without sanitization when the driver composes the target namespace for an operation. An application that incorporates untrusted input into these name components can have operations directed at a resource other than the one intended.",
    "evidence": "osv:CVE-2026-81524",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2026-81524",
      "aliases": [
        "CVE-2026-81524"
      ],
      "metrics": [
        {
          "type": "CVSS_V4",
          "score": "CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:L/VA:N/SC:N/SI:N/SA:N"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mongodb/mongo-c-driver",
              "type": "GIT",
              "events": [
                {
                  "introduced": "e1bf9e0ae933f1a09a0ad435632f330acafe2f18"
                },
                {
                  "fixed": "0ecd80a7b40998d48738452eb6be013bf3b9997e"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "fixed": "2.5.1"
                      }
                    ],
                    "source": "AFFECTED_FIELD",
                    "strategy": "StandardRange"
                  },
                  {
                    "range": [
                      {
                        "fixed": "0ecd80a7b40998d48738452eb6be013bf3b9997e"
                      }
                    ],
                    "source": "REFERENCES_TAG",
                    "original_tag": "2.5.1"
                  },
                  {
                    "cpe": "cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:*",
                    "range": [
                      {
                        "introduced": "1.0.0"
                      },
                      {
                        "fixed": "2.5.1"
                      }
                    ],
                    "source": "CPE_RANGE"
                  }
                ]
              }
            }
          ],
          "versions": [
            "2.5.0",
            "1.11.0",
            "1.9.0-rc1",
            "1.9.0-rc0",
            "1.7.0-rc0",
            "1.6.0",
            "1.6.0-rc0",
            "1.5.0-rc4",
            "1.5.0-rc3",
            "1.5.0-rc2",
            "1.5.0-rc1",
            "1.5.0-rc0",
            "1.4.0-beta1",
            "1.3.0",
            "1.3.0-rc0",
            "1.1.11",
            "1.1.10",
            "1.1.9",
            "1.1.8",
            "1.1.7",
            "1.1.6",
            "1.1.5",
            "1.1.4",
            "1.1.2",
            "1.1.0",
            "1.1.0-rc0",
            "1.0.2",
            "1.0.0"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-81524.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:29.216246020Z",
      "provider": "osv",
      "references": [
        "https://github.com/mongodb/mongo-c-driver/releases/tag/2.5.1",
        "https://jira.mongodb.org/browse/CDRIVER-6424",
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81524.json",
        "https://nvd.nist.gov/vuln/detail/CVE-2026-81524"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-99"
        ],
        "cna_assigner": "mongodb",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/81xxx/CVE-2026-81524.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2026-81524",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 496280,
  "published_at": "2026-08-27T18:32:25.355+00:00"
}