{"id":"CVE-2021-24020","aliases":["EUVD-2021-10940","GHSA-8wr8-gr7j-v6cg"],"status":"published","title":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4...","description":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.","severity":{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00616,"percentile":0.49837,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-326","CWE-347"],"published":"2021-07-09T18:17:26Z","modified":"2026-06-17T03:39:10Z","products":[{"vendor":"fortinet","product":"fortimail"},{"vendor":"fortinet","product":"fortinet fortimail"}],"references":[{"url":"https://fortiguard.com/advisory/FG-IR-21-027","tags":["x_refsource_CONFIRM","x_transferred","Vendor Advisory"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2021-24020"},{"url":"https://github.com/advisories/GHSA-8wr8-gr7j-v6cg"}],"sources":{"cve":[{"id":"CVE-2021-24020","description":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.","status":"published","published":"2021-07-09T18:17:26Z","modified":"2024-10-25T13:57:25.857Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"cna"}],"updated_at":"2026-11-02T14:33:04.679189Z"}],"euvd":[{"id":"EUVD-2021-10940","description":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.","status":"published","published":"2021-07-09T18:17:26Z","modified":"2024-10-25T13:57:25Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high"}],"updated_at":"2026-11-03T00:05:18.633679Z"}],"ghsa":[{"id":"GHSA-8wr8-gr7j-v6cg","title":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4...","description":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.","status":"published","published":"2022-05-24T19:07:19Z","modified":"2023-01-27T05:03:02Z","cvss":[{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical"}],"cwes":["CWE-326"],"updated_at":"2026-11-02T14:42:09.625504Z"}],"nvd":[{"id":"CVE-2021-24020","description":"A missing cryptographic step in the implementation of the hash digest algorithm in FortiMail 6.4.0 through 6.4.4, and 6.2.0 through 6.2.7 may allow an unauthenticated attacker to tamper with signed URLs by appending further data which allows bypass of signature verification.","status":"published","published":"2021-07-09T19:15:08.197Z","modified":"2026-06-17T03:39:10.277Z","cvss":[{"version":"3.1","score":7.5,"vector":"CVSS:3.1/AV:N/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H","level":"high","assessor":"secondary"},{"version":"3.1","score":9.8,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","level":"critical","assessor":"primary"},{"version":"2.0","score":7.5,"vector":"AV:N/AC:L/Au:N/C:P/I:P/A:P","level":"high","assessor":"primary"}],"cwes":["CWE-347"],"updated_at":"2026-11-02T14:06:55.259633Z"}]}}