{
  "affected": [
    {
      "ranges": [
        {
          "database_specific": {
            "cpe": "cpe:2.3:a:mongodb:c_driver:*:*:*:*:*:mongodb:*:*",
            "extracted_events": [
              {
                "introduced": "1.30.0"
              },
              {
                "fixed": "1.30.9"
              },
              {
                "introduced": "2.0.0"
              },
              {
                "fixed": "2.5.2"
              }
            ],
            "source": "CPE_RANGE"
          },
          "events": [
            {
              "introduced": "be3955bb98ecabeb8e2873804f3345250e9bff60"
            },
            {
              "fixed": "f64476433230847fb0f43afaeb7be048eb817f8b"
            },
            {
              "introduced": "67817df0a9ed11b07e457477e6db1384da9421c4"
            },
            {
              "fixed": "52ffca1e649b597c51162b5b3b37f057b73b059d"
            }
          ],
          "repo": "https://github.com/mongodb/mongo-c-driver",
          "type": "GIT"
        }
      ]
    }
  ],
  "database_specific": {
    "cna_assigner": "mongodb",
    "cwe_ids": [
      "CWE-787"
    ],
    "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84969.json",
    "unresolved_ranges": [
      {
        "extracted_events": [
          {
            "introduced": "1.30.0"
          },
          {
            "fixed": "1.30.9"
          },
          {
            "introduced": "2.0.0"
          },
          {
            "fixed": "2.5.2"
          }
        ],
        "source": "AFFECTED_FIELD"
      }
    ]
  },
  "details": "A memory-handling error in the BSON-to-JSON conversion helpers of the MongoDB C Driver can write a small number of bytes past the end of a heap buffer when a binary field is encoded and the output is cut short at a caller-configured length limit. A party who supplies the document content, with no privileges on the application that links the driver, may cause a small amount of data outside the intended buffer to be altered.",
  "id": "CVE-2026-84969",
  "modified": "2026-09-12T03:31:06.289094449Z",
  "published": "2026-09-03T14:59:01.427Z",
  "references": [
    {
      "type": "WEB",
      "url": "https://jira.mongodb.org/browse/CDRIVER-6410"
    },
    {
      "type": "ADVISORY",
      "url": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/84xxx/CVE-2026-84969.json"
    },
    {
      "type": "ADVISORY",
      "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-84969"
    }
  ],
  "schema_version": "1.9.0",
  "severity": [
    {
      "score": "CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:L/VA:N/SC:N/SI:N/SA:N",
      "type": "CVSS_V4"
    }
  ],
  "summary": "Heap overflow via truncated base64 encoding of binary fields in length-limited JSON output"
}