MantisBT is Vulnerable to Denial-of-Service (DoS) attack via Excessive Note Length

{
  "id": "098a6ba2b3b83cb497e515623f92b7fafe377cfef2e0b7ddfb72e34b026e22a5",
  "url": "https://osv.dev/vulnerability/CVE-2025-46556",
  "method": "structured",
  "payload": {
    "kind": "advisory",
    "title": "MantisBT is Vulnerable to Denial-of-Service (DoS) attack via Excessive Note Length",
    "summary": "Mantis Bug Tracker (MantisBT) is an open source issue tracker. Versions 2.27.1 and below allow attackers to permanently corrupt issue activity logs by submitting extremely long notes (tested with 4,788,761 characters) due to a lack of server-side validation of note length. Once such a note is added, the activity stream UI fails to render; therefore, new notes cannot be displayed, effectively breaking all future collaboration on the issue. This issue is fixed in version 2.27.2.",
    "evidence": "osv:CVE-2025-46556",
    "products": [],
    "severity": "medium",
    "structured": {
      "id": "CVE-2025-46556",
      "aliases": [
        "CVE-2025-46556",
        "GHSA-r3jf-hm7q-qfw5"
      ],
      "metrics": [
        {
          "type": "CVSS_V3",
          "score": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H"
        }
      ],
      "affected": [
        {
          "ranges": [
            {
              "repo": "https://github.com/mantisbt/mantisbt",
              "type": "GIT",
              "events": [
                {
                  "introduced": "0"
                },
                {
                  "fixed": "a90611fb8939e72d2dab5e3a611127974a0e1929"
                },
                {
                  "fixed": "c99a41272532ba49b5c8dccb7797afead9864234"
                },
                {
                  "fixed": "d5cec6bffb44d54bd412c186b9baa409b1aa4238"
                },
                {
                  "fixed": "e9119c68b4a0eaa0bbde3deb121e81f5f7157361"
                }
              ],
              "database_specific": {
                "extracted_events": [
                  {
                    "cpe": "cpe:2.3:a:mantisbt:mantisbt:*:*:*:*:*:*:*:*",
                    "range": [
                      {
                        "introduced": "0"
                      },
                      {
                        "fixed": "2.27.2"
                      }
                    ],
                    "source": "CPE_RANGE"
                  },
                  {
                    "range": [
                      {
                        "fixed": "c99a41272532ba49b5c8dccb7797afead9864234"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "d5cec6bffb44d54bd412c186b9baa409b1aa4238"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  },
                  {
                    "range": [
                      {
                        "fixed": "e9119c68b4a0eaa0bbde3deb121e81f5f7157361"
                      }
                    ],
                    "source": "REFERENCES_COMMIT"
                  }
                ]
              }
            }
          ],
          "versions": [
            "release-2.27.1",
            "release-2.27.0",
            "release-2.26.0",
            "release-2.25.0",
            "release-2.24.0",
            "release-2.23.0",
            "release-2.22.0",
            "release-2.21.0",
            "release-2.20.0",
            "release-2.19.0",
            "release-2.18.0",
            "release-2.17.0",
            "release-2.16.0",
            "release-2.15.0",
            "release-2.14.0",
            "release-2.13.0",
            "release-2.12.0",
            "release-2.11.0",
            "release-2.10.0",
            "release-2.9.0",
            "release-2.8.0",
            "release-2.7.0",
            "release-2.6.0",
            "release-2.5.0",
            "release-2.4.0",
            "release-2.3.0",
            "release-2.2.0",
            "release-2.1.0",
            "release-2.0.0",
            "release-2.0.0-rc.2",
            "release-2.0.0-rc.1",
            "release-2.0.0-beta.3",
            "release-2.0.0-beta.2",
            "release-2.0.0-beta.1",
            "release-1.3.0-rc.2",
            "release-1.3.0-rc.1",
            "release-1.3.0-beta.3",
            "release-1.3.0-beta.2",
            "release-1.3.0-beta.1",
            "release-1.2.0rc1",
            "release-1.2.0a3",
            "release-1.2.0a2",
            "release-1.2.0a1"
          ],
          "database_specific": {
            "source": "https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2025-46556.json"
          }
        }
      ],
      "modified": "2026-10-28T02:30:45.909209554Z",
      "provider": "osv",
      "references": [
        "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46556.json",
        "https://github.com/mantisbt/mantisbt/security/advisories/GHSA-r3jf-hm7q-qfw5",
        "https://nvd.nist.gov/vuln/detail/CVE-2025-46556",
        "https://github.com/mantisbt/mantisbt/commit/c99a41272532ba49b5c8dccb7797afead9864234",
        "https://github.com/mantisbt/mantisbt/commit/d5cec6bffb44d54bd412c186b9baa409b1aa4238",
        "https://github.com/mantisbt/mantisbt/commit/e9119c68b4a0eaa0bbde3deb121e81f5f7157361"
      ],
      "provider_metadata": {
        "cwe_ids": [
          "CWE-770"
        ],
        "cna_assigner": "GitHub_M",
        "osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46556.json"
      }
    },
    "related_cves": [
      {
        "value": "CVE-2025-46556",
        "evidence": "/id"
      }
    ],
    "security_relevant": true,
    "severity_evidence": "/severity/0/score"
  },
  "source_id": "core-osv",
  "document_id": 514267,
  "published_at": "2025-11-04T00:20:28.193+00:00"
}