CVE-2026-34721 PUBLISHED

Zammad has Cross-site request forgery (CSRF) in OAuth callback endpoints

Assigner: GitHub_M
Reserved: 30.03.2026 Published: 08.04.2026 Updated: 08.04.2026

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the OAuth callback endpoints for Microsoft, Google, and Facebook external credentials do not validate a CSRF state parameter. This vulnerability is fixed in 7.0.1 and 6.5.4.

Metrics

CVSS 4.0

CVSS Vector: CVSS:4.0/AV:N/AC:H/AT:P/PR:L/UI:P/VC:L/VI:H/VA:N/SC:N/SI:N/SA:N
CVSS Score: 5.9

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	Low	Confidentiality	None
Attack Complexity	High	Integrity	High	Integrity	None
Attack Requirements	Present	Availability	None	Availability	None
Privileges Required	Low
User Interaction	Passive

CVSS 4.0

Product Status

Vendor	zammad
Product	zammad
Versions	Version < 6.5.4 is affected Version >= 7.0.0-alpha, < 7.0.1 is affected

References

https://github.com/zammad/zammad/security/advisories/GHSA-mfwp-hx66-626c

Problem Types

CWE-352: Cross-Site Request Forgery (CSRF) CWE