CVE-2026-63205

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.

CVSS

No CVSS.

References

Link	Resource
https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44
https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5

Configurations

No configuration.

History

25 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 19:17

Updated : 2026-09-29 20:17

NVD link : CVE-2026-63205

Mitre link : CVE-2026-63205

CVE.ORG link : CVE-2026-63205

JSON object : View

Products Affected

No product.

CWE

CWE-639

Authorization Bypass Through User-Controlled Key

CWE-862

Missing Authorization

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