# CVE-2026-63205: Zammad authorization bypass via email signature attachments

Source: https://junglewise.ai/threats/cve-2026-63205-zammad-is-a-web-based-open-source-helpdesk-customer-support  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-09-25. Updated: 2026-09-26  
License: CC BY 4.0 with a link back

CVE-2026-63205 · Severity: info · Published 2026-09-25

Zammad is a web-based helpdesk system that processes images referenced in email signatures. Channel administrators can exploit a flaw in signature creation to copy and download attachments they shouldn't have access to—such as files from tickets in groups they don't belong to. An attacker with channel admin permissions can read sensitive attachments by embedding references to them in a signature, bypassing normal access controls.

Technologies: [Zammad](https://junglewise.ai/threats/technologies/zammad). Vendors: [Zammad](https://junglewise.ai/threats/vendors/zammad).

## Quick answers

**Is CVE-2026-63205 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-63205 being exploited in the wild.

**How severe is CVE-2026-63205?** Informational severity, published 25 September 2026.

**Which products and versions are affected?** Zammad prior to 7.1.2.

**Is there a fix for CVE-2026-63205?** A patch was published on 2026-08-04: Version 7.1.2 released (GitHub advisory date indicates fix was available earlier) Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-63205 attacked?** It is attacked over the network, in a web application.

**Am I affected by CVE-2026-63205?** Check whether you run Zammad at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

When Zammad creates or updates an email signature containing inline images (HTML img tags), it copies referenced attachments without verifying the user has permission to access the original. The copied attachment is owned by the signature object, so attachment access control checks are bypassed; permissions are evaluated against the signature (which the admin created) rather than the original object. An authenticated user with admin.channel_email, admin.channel_google, admin.channel_microsoft365, or admin.channel_microsoft_graph role can exploit this to read attachments from restricted tickets or knowledge-base articles.

## Affected products

- Zammad Zammad prior to 7.1.2

## Timeline

- 2026-09-25: disclosed
- 2026-08-04: patched: Version 7.1.2 released (GitHub advisory date indicates fix was available earlier)

## References

- [https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44](https://github.com/zammad/zammad/commit/f3e4da83621efad8443a4e9fe6bd87befad47c44)
- [https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5](https://github.com/zammad/zammad/security/advisories/GHSA-pp8r-x7pp-5qj5)

## Related threats

- [Zammad stored cross-site scripting in ticket article rendering](https://junglewise.ai/threats/cve-2026-102345-zammad-is-a-web-based-open-source-helpdesk-customer-support)
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- [Zammad S/MIME signature verification bypass allows sender impersonation](https://junglewise.ai/threats/cve-2026-84465-zammad-is-a-web-based-open-source-helpdesk-customer-support)
- [Zammad unauthorized data access in External Data Source](https://junglewise.ai/threats/cve-2026-84464-zammad-is-a-web-based-open-source-helpdesk-customer-support)