CVE-2026-63206

Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, zammad's HTML sanitizer, which blocks remote images in ticket articles and email views, can be bypassed using a shortened URL format that omits the double slash after the scheme (for example a shortened HTTP URL instead of a shortened HTTP URL). Modern browsers treat both forms as equivalent remote URLs. As a result, an attacker who sends a crafted email or ticket can cause the recipient's browser to silently load an image from an external server, revealing when and by whom the ticket was opened. Zammad's "remote content blocked" warning is not shown because the sanitizer does not recognize the shortened form as remote. This issue is fixed in version 7.1.2.

CVSS

No CVSS.

References

Link	Resource
https://github.com/zammad/zammad/commit/a5878f37e4010f0b3bec85dae35af964cc1c8019
https://github.com/zammad/zammad/security/advisories/GHSA-fpwp-w2p4-hqg7

Configurations

No configuration.

History

25 Sep 2026, 19:17

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-09-25 19:17

Updated : 2026-09-28 14:45

NVD link : CVE-2026-63206

Mitre link : CVE-2026-63206

CVE.ORG link : CVE-2026-63206

JSON object : View

Products Affected

No product.

CWE

CWE-20

Improper Input Validation

CWE-184

Incomplete List of Disallowed Inputs

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