{"schema_version":"1","data":[{"id":3901,"advisory_id":"0c5f9479-c2dd-4f44-ad28-d16164d918fa","revision":1,"source_id":"core-cve","source_url":"https://www.cve.org/CVERecord?id=CVE-2026-84465","source_published_at":"2026-09-25T18:19:58.735+00:00","published_at":"2026-10-24T21:42:57.352936+00:00","extraction_method":"structured","technologies":["core-cve","zammad"],"cve_ids":["CVE-2026-84465"],"event_types":["advisory"],"payload":{"kind":"advisory","title":"Zammad: S/MIME signature verification allows forged sender impersonation","summary":"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.","evidence":"cve:CVE-2026-84465","products":[{"name":{"value":"zammad","evidence":"/containers/cna/affected/0/product"},"prerequisites":[],"fixed_versions":[],"affected_versions":[]}],"severity":"high","structured":{"id":"CVE-2026-84465","aliases":["CVE-2026-84465"],"metrics":[{"cvssV4_0":{"version":"4.0","baseScore":7.1,"attackVector":"NETWORK","baseSeverity":"HIGH","vectorString":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:P/VC:N/VI:H/VA:N/SC:N/SI:N/SA:N","userInteraction":"PASSIVE","attackComplexity":"LOW","attackRequirements":"NONE","privilegesRequired":"NONE","subIntegrityImpact":"NONE","vulnIntegrityImpact":"HIGH","subAvailabilityImpact":"NONE","vulnAvailabilityImpact":"NONE","subConfidentialityImpact":"NONE","vulnConfidentialityImpact":"NONE"}}],"affected":[{"vendor":"zammad","product":"zammad","versions":[{"status":"affected","version":"< 7.1.2"}]}],"modified":"2026-09-29T18:08:05.375Z","provider":"cve","references":["https://github.com/zammad/zammad/security/advisories/GHSA-m9ff-hjr3-93h4","https://github.com/zammad/zammad/commit/9a07d0b8214ac4e8e10c23fce71d613bd0625524"],"provider_metadata":{"adp":[{"title":"CISA ADP Vulnrichment","metrics":[{"other":{"type":"ssvc","content":{"id":"CVE-2026-84465","role":"CISA Coordinator","options":[{"Exploitation":"none"},{"Automatable":"yes"},{"Technical Impact":"partial"}],"version":"2.0.3","timestamp":"2026-09-29T18:07:09.159774Z"}}}],"providerMetadata":{"orgId":"134c704f-9b21-4f2e-91b3-4a467353bcc0","shortName":"CISA-ADP","dateUpdated":"2026-09-29T18:08:05.375Z"}}],"cna":{"orgId":"a0819718-46f1-4df5-94e2-005712e83aaa","shortName":"GitHub_M","dateUpdated":"2026-09-25T18:19:58.735Z"}}},"related_cves":[{"value":"CVE-2026-84465","evidence":"/cveMetadata/cveId"}],"security_relevant":true,"severity_evidence":"/containers/cna/metrics"}}],"next_after":3901,"next_before":3901}