CVE-2026-63205 (GCVE-0-2026-63205)

Vulnerability from cvelistv5 – Published: 2026-09-25 18:13 – Updated: 2026-09-29 19:40
VLAI
Title
Zammad: Channel admins can read unauthorized attachments via signature rich-text body
Summary
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.
Severity
5.1 (Medium)
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
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-09-29 19:40 UTC
CWE
  • CWE-639 - Authorization Bypass Through User-Controlled Key
  • CWE-862 - Missing Authorization
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 7886 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
zammad zammad Affected: < 7.1.2
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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