Vulnerability · Published Sep 25, 2026 · Assigned by GitHub_M

CVE-2026-56728Zammad: Cross-User Taskbar Item Access Control Vulnerability

Medium 5.3

In plain English

A medium-severity information exposure in zammad from zammad. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.3% (higher than 26% of all known vulnerabilities).

Severity (CVSS 4.0)5.3Medium

Exploit odds (30 days)0.3%top 73.8% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.2, a broken access control vulnerability exists in Zammad's GraphQL API. An authenticated user can access taskbar item data belonging to another user by crafting a request with the target user's taskbar identifier. The taskbar feature stores transient state for active user sessions, including auto-saved ticket drafts. Under certain conditions, the authorization check for taskbar item access is not enforced, allowing a user to read another user's taskbar item data. This vulnerability is fixed in 7.0.2.

Affected products (as reported)

Vendor	Product	Versions
zammad	zammad	< 7.0.2

Weakness: CWE-200, CWE-639 · Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N

References

https://github.com/zammad/zammad/security/advisories/GHSA-jvcg-5539-vvc3 x_refsource_CONFIRM
https://github.com/zammad/zammad/commit/4ccd5d573023b66b0d0184914c92417e1780793f x_refsource_MISC
https://github.com/zammad/zammad/releases/tag/7.0.2 x_refsource_MISC