{"id":"CVE-2025-46556","aliases":["EUVD-2025-37509","GHSA-r3jf-hm7q-qfw5"],"status":"published","title":"MantisBT is Vulnerable to Denial-of-Service (DoS) attack via Excessive Note Length","description":"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.","severity":{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-11","score":0.00411,"percentile":0.35867,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":true},"cwes":["CWE-770"],"published":"2025-11-03T17:07:39Z","modified":"2026-10-28T02:30:45Z","fixes":[{"ecosystem":"Packagist","package":"mantisbt/mantisbt","fixed_in":["2.27.2"],"sources":["ghsa","osv"]}],"affected":[{"source":"ghsa","ecosystem":"Packagist","package":"mantisbt/mantisbt","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.27.2"}]}]},{"source":"osv","ecosystem":"Packagist","package":"mantisbt/mantisbt","ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.27.2"}]}],"versions":["2.10.0","2.10.1","2.11.0","2.11.1","2.12.0","2.12.1","2.12.2","2.13.0","2.13.1","2.13.2","2.14.0","2.15.0","2.15.1","2.16.0","2.16.1","2.17.0","2.17.1","2.17.2","2.18.0","2.18.1","2.19.0","2.19.1","2.20.0","2.20.1","2.21.0","2.21.1","2.21.2","2.21.3","2.22.0","2.22.1","2.22.2","2.23.0","2.23.1","2.24.0","2.24.1","2.24.2","2.24.3","2.24.4","2.24.5","2.25.0","2.25.1","2.25.2","2.25.3","2.25.4","2.25.5","2.25.6","2.25.7","2.25.8","2.26.0","2.26.1","2.26.2","2.26.3","2.26.4","2.27.0","2.27.1","2.3.0","2.3.1","2.3.2","2.3.3","2.4.0","2.4.1","2.4.2","2.5.0","2.5.1","2.5.2","2.6.0","2.7.0","2.7.1","2.8.0","2.8.1","2.9.0","2.9.1"]}],"products":[{"vendor":"mantisbt","product":"mantisbt"}],"references":[{"url":"https://github.com/mantisbt/mantisbt/security/advisories/GHSA-r3jf-hm7q-qfw5","tags":["x_refsource_CONFIRM","Vendor Advisory","advisory","web"]},{"url":"https://github.com/mantisbt/mantisbt/commit/c99a41272532ba49b5c8dccb7797afead9864234","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/mantisbt/mantisbt/commit/d5cec6bffb44d54bd412c186b9baa409b1aa4238","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://github.com/mantisbt/mantisbt/commit/e9119c68b4a0eaa0bbde3deb121e81f5f7157361","tags":["x_refsource_MISC","Patch","fix","web"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2025-46556","tags":["advisory"]},{"url":"https://github.com/advisories/GHSA-r3jf-hm7q-qfw5"},{"url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2025/46xxx/CVE-2025-46556.json","tags":["advisory"]},{"url":"https://github.com/mantisbt/mantisbt","tags":["package"]}],"sources":{"cve":[{"id":"CVE-2025-46556","title":"MantisBT is Vulnerable to Denial-of-Service (DoS) attack via Excessive Note Length","description":"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.","status":"published","published":"2025-11-04T00:20:28.193Z","modified":"2025-11-06T20:44:40.1Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"cna"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:32:36.385228Z"}],"euvd":[{"id":"EUVD-2025-37509","description":"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.","status":"published","published":"2025-11-04T00:20:28Z","modified":"2025-11-06T20:44:40Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"updated_at":"2026-11-02T19:49:19.806495Z"}],"ghsa":[{"id":"GHSA-r3jf-hm7q-qfw5","title":"MantisBT Vulnerable to Denial-of-Service (DoS) via Excessive Note Length","description":"A lack of server-side validation for note length in MantisBT allows attackers to permanently corrupt issue activity logs by submitting extremely long notes (tested with 4,788,761 characters). Once such a note is added:\n\n### Impact\n- The entire activity stream becomes unviewable (UI fails to render).\n- New notes cannot be displayed, effectively breaking all future collaboration on the issue.\n\n### Patches\nFixed in 2.27.2.\n\n### Workarounds\nNone\n\n### Credits\nThanks to Mazen Mahmoud (@TheAmazeng) for reporting the vulnerability.","status":"published","published":"2025-11-03T17:07:39Z","modified":"2025-11-04T16:55:31Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:39:06.376137Z"}],"nvd":[{"id":"CVE-2025-46556","description":"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.","status":"published","published":"2025-11-04T01:15:33.257Z","modified":"2026-10-19T13:10:00.11Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium","assessor":"secondary"},{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","level":"high","assessor":"primary"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T14:11:41.607433Z"}],"osv":[{"id":"CVE-2025-46556","title":"MantisBT is Vulnerable to Denial-of-Service (DoS) attack via Excessive Note Length","description":"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.","status":"published","published":"2025-11-04T00:20:28.193Z","modified":"2026-10-28T02:30:45.909209554Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:44:49.707645Z"},{"id":"GHSA-r3jf-hm7q-qfw5","title":"MantisBT Vulnerable to Denial-of-Service (DoS) via Excessive Note Length","description":"A lack of server-side validation for note length in MantisBT allows attackers to permanently corrupt issue activity logs by submitting extremely long notes (tested with 4,788,761 characters). Once such a note is added:\n\n### Impact\n- The entire activity stream becomes unviewable (UI fails to render).\n- New notes cannot be displayed, effectively breaking all future collaboration on the issue.\n\n### Patches\nFixed in 2.27.2.\n\n### Workarounds\nNone\n\n### Credits\nThanks to Mazen Mahmoud (@TheAmazeng) for reporting the vulnerability.","status":"published","published":"2025-11-03T17:07:39Z","modified":"2025-11-04T17:17:47.06093Z","cvss":[{"version":"3.1","score":6.5,"vector":"CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H","level":"medium"}],"cwes":["CWE-770"],"updated_at":"2026-11-02T15:46:55.122811Z"}]}}