Medium severity · published Apr 8, 2026
CVE-2026-34721
Zammad has Cross-site request forgery (CSRF) in OAuth callback endpoints
6.5
CVSS
0.1%
EPSS
No
On KEV
Description
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
Required
Confidentiality
High
Integrity
None
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.1% · higher than 1% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
ZA
zammad · zammad
< 6.5.4; >= 7.0.0-alpha, < 7.0.1 · source: vendor, NVD
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-34721
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-34721
Vendor Advisory
https://github.com/zammad/zammad/security/advisories/GHSA-mfwp-hx66-626c
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