{"id":"CVE-2026-29140","aliases":["EUVD-2026-18160","GHSA-mmr3-c33j-h2f2"],"status":"published","title":"S/MIME Signature Additional Certificate","description":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.","severity":{"version":"4.0","score":7.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N","level":"high","assessor":"cna","from":"cve"},"epss":{"day":"2026-11-10","score":0.00122,"percentile":0.02018,"model":"v2026.06.15"},"facts":{"in_kev":false,"known_exploited":false,"public_exploit":false,"fix_available":false},"cwes":["CWE-295"],"published":"2026-04-02T08:27:52Z","modified":"2026-10-26T21:10:00Z","products":[{"vendor":"seppmail","product":"secure email gateway"},{"vendor":"seppmail","product":"secure_email_gateway"},{"vendor":"seppmail ag","product":"secure email gateway"}],"references":[{"url":"https://downloads.seppmail.com/extrelnotes/150/ERN15.0.html#seppmail-vulnerability-disclosure-1503","tags":["release-notes","Release Notes"]},{"url":"https://nvd.nist.gov/vuln/detail/CVE-2026-29140"},{"url":"https://github.com/advisories/GHSA-mmr3-c33j-h2f2"}],"sources":{"cve":[{"id":"CVE-2026-29140","title":"S/MIME Signature Additional Certificate","description":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.","status":"published","published":"2026-04-02T08:27:52.154Z","modified":"2026-04-02T14:48:53.216Z","cvss":[{"version":"4.0","score":7.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N","level":"high","assessor":"cna"}],"cwes":["CWE-295"],"updated_at":"2026-11-02T14:19:56.284359Z"}],"euvd":[{"id":"EUVD-2026-18160","description":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.","status":"published","published":"2026-04-02T08:27:52Z","modified":"2026-04-02T14:48:53Z","cvss":[{"version":"4.0","score":7.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N","level":"high"}],"updated_at":"2026-11-02T19:25:23.121433Z"}],"ghsa":[{"id":"GHSA-mmr3-c33j-h2f2","title":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker...","description":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.","status":"published","published":"2026-04-02T09:30:25Z","modified":"2026-04-16T21:32:15Z","cvss":[{"version":"4.0","score":7.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium"}],"cwes":["CWE-295"],"updated_at":"2026-11-02T15:07:31.795355Z"}],"nvd":[{"id":"CVE-2026-29140","description":"SEPPmail Secure Email Gateway before version 15.0.3 allows an attacker to cause attacker-controlled certificates to be used for future encryption to a victim by adding the certificates to S/MIME signatures.","status":"published","published":"2026-04-02T09:16:22.623Z","modified":"2026-10-26T21:10:00.17Z","cvss":[{"version":"4.0","score":7.7,"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:L/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X","level":"high","assessor":"secondary"},{"version":"3.1","score":5.3,"vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:L/A:N","level":"medium","assessor":"primary"}],"cwes":["CWE-295"],"updated_at":"2026-11-02T14:12:12.73929Z"}]}}