{"schema":"threatline.record/2","record":{"id":"CVE-2026-84465","aliases":["GHSA-m9ff-hjr3-93h4"],"summary":"Zammad: S/MIME signature verification allows forged sender impersonation","details":"Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when Zammad checks the digital signature on an incoming S/MIME-signed email, it does not verify that the signing certificate is genuinely trusted, it only checks whether a certificate with a matching name is already stored in the system. An attacker can create their own certificate using the name of a real, previously trusted sender and use it to send a forged email. Zammad will display that email with the same \"validly signed\" indicator as a genuine message from the real sender, even though the attacker never had access to that sender's actual certificate or private key. This issue is fixed in version 7.1.2.","categories":["Applications & CMS"],"product":"zammad","vendor":"zammad","ecosystem":null,"affected_ranges":[{"source":"CVE List","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-84465","source_modified_at":"2026-09-29T18:08:05.375Z","fetched_at":"2026-10-23T18:52:38.922436Z","product":"zammad","vendor":"zammad","versions":[{"version":"< 7.1.2","status":"affected"}],"defaultStatus":null}],"fixed_versions":[],"cvss":7.1,"severity":"High","kev":{"listed":false},"epss":{"probability":0.00124,"percentile":0.0193,"score_date":"2026-10-23"},"published_at":"2026-09-25T18:19:58.735Z","modified_at":"2026-09-29T18:08:05.375Z","provenance":[{"source":"CVE List","url":"https://www.cve.org/CVERecord?id=CVE-2026-84465","fetched_at":"2026-10-23T18:52:38.922436Z","source_modified_at":"2026-09-29T18:08:05.375Z"},{"source":"EPSS","url":"https://api.first.org/data/v1/epss?cve=CVE-2026-84465","fetched_at":"2026-10-23T18:42:43.628194Z","source_modified_at":"2026-10-23"}],"sources":["CVE List","EPSS"],"references":[{"source":"CVE List","url":"https://github.com/zammad/zammad/security/advisories/GHSA-m9ff-hjr3-93h4","tags":["x_refsource_CONFIRM"]},{"source":"CVE List","url":"https://github.com/zammad/zammad/commit/9a07d0b8214ac4e8e10c23fce71d613bd0625524","tags":["x_refsource_MISC"]}],"locations":[],"motoko_assessment":{"status":"requires_architecture_review","automatic_remediation":false},"cve_state":"PUBLISHED","cvss_source":"CVE List","ssvc":{"exploitation":"none","automatable":"yes","technical_impact":"partial","assessed_at":"2026-09-29T18:07:09.159774Z"},"classification":{"method":"product-first software-layer rules","rules_version":"2.1","matched_on":"product","confidence":"heuristic","reviewed":false},"change_timestamp":"2026-09-29T18:08:05.375Z","content_hash":"64eb70621a5d206c686eac0ca2e71be3d441262138c10321b3665918b8eabb7e"}}