{"id":"CVE-2026-63205","summary":"Zammad: Channel admins can read unauthorized attachments via signature rich-text body","details":"Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, when creating or updating an email signature, Zammad processes inline images referenced in the signature body. If a signature body contains an HTML img tag pointing to any existing attachment, the system copies that attachment into a new signature-owned record, without checking whether the user has permission to access the original attachment. The newly created copy is then downloadable by the same channel-admin user, because attachment access is determined by the copy's owner (the signature), not the original object (e.g., a ticket or knowledge-base article). This allows a user with any of the admin.channel_email, admin.channel_google, admin.channel_microsoft365, or admin.channel_microsoft_graph permissions to read attachments they would otherwise be denied access to, such as ticket attachments belonging to groups they are not a member of. This issue is fixed in version 7.1.2.","aliases":["GHSA-pp8r-x7pp-5qj5"],"modified":"2026-09-27T03:47:27.966482634Z","published":"2026-09-25T18:13:25.176Z","database_specific":{"osv_generated_from":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63205.json","cna_assigner":"GitHub_M","cwe_ids":["CWE-639","CWE-862"]},"references":[{"type":"ADVISORY","url":"https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/63xxx/CVE-2026-63205.json"},{"type":"ADVISORY","url":"https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2026-63205"},{"type":"FIX","url":"https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/zammad/zammad","events":[{"introduced":"0"},{"fixed":"f3e4da83621efad8443a4e9fe6bd87befad47c44"}],"database_specific":{"extracted_events":[{"introduced":"0"},{"fixed":"7.1.2"}],"source":["AFFECTED_FIELD","REFERENCES"]}}],"versions":["7.1.1","7.1.0","7.1.0-alpha","7.0.0-alpha","6.6.0-alpha","6.5.0-alpha","6.4.0-alpha","6.3.0-alpha","6.2.0-alpha","6.1.0-alpha","6.0.0-alpha","5.5.0-alpha","5.4.0-alpha","5.3.0-alpha","5.2.0-alpha","3.7.0","1.6.0"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2026-63205.json"}}],"schema_version":"1.9.0","severity":[{"type":"CVSS_V4","score":"CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N"}]}