{"api_version":"1","generated_at":"2026-09-25T22:11:42+00:00","cve":"CVE-2026-84465","urls":{"html":"https://cve.report/CVE-2026-84465","api":"https://cve.report/api/cve/CVE-2026-84465.json","docs":"https://cve.report/api","cve_org":"https://www.cve.org/CVERecord?id=CVE-2026-84465","nvd":"https://nvd.nist.gov/vuln/detail/CVE-2026-84465"},"summary":{"title":"Zammad: S/MIME signature verification allows forged sender impersonation","description":"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. 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