Zammad up to 6.5.3/7.0.0 OAuth Callback Endpoint cross-site request forgery

CVSS Meta Temp Score
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Current Exploit Price (≈)
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CTI Interest Score
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4.1$0-$5k0.74-

Summaryinfo

A vulnerability was found in Zammad up to 6.5.3/7.0.0. It has been classified as problematic. Affected is an unknown function of the component OAuth Callback Endpoint. The manipulation leads to cross-site request forgery. This vulnerability is listed as CVE-2026-34721. The attack may be initiated remotely. There is no available exploit. Upgrading the affected component is recommended.

Detailsinfo

A vulnerability was found in Zammad up to 6.5.3/7.0.0 and classified as problematic. This issue affects an unknown code block of the component OAuth Callback Endpoint. The manipulation with an unknown input leads to a cross-site request forgery vulnerability. Using CWE to declare the problem leads to CWE-352. The web application does not, or can not, sufficiently verify whether a well-formed, valid, consistent request was intentionally provided by the user who submitted the request. Impacted is integrity. The summary by CVE is:

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.

The advisory is shared at github.com. The identification of this vulnerability is CVE-2026-34721 since 03/30/2026. The exploitation is known to be easy. The attack may be initiated remotely. No form of authentication is needed for a successful exploitation. It demands that the victim is doing some kind of user interaction. Neither technical details nor an exploit are publicly available.

Upgrading to version 6.5.4 or 7.0.1 eliminates this vulnerability.

The vulnerability is also documented in the vulnerability database at CERT Bund (WID-SEC-2026-1000). If you want to get the best quality for vulnerability data then you always have to consider VulDB.

Affected

  • Zammad Zammad

Productinfo

Name

Version

License

Website

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 4.3
VulDB Meta Temp Score: 4.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross-site request forgery
CWE: CWE-352 / CWE-862 / CWE-863
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: Zammad 6.5.4/7.0.1

Timelineinfo

03/30/2026 CVE reserved
04/08/2026 +9 days Advisory disclosed
04/08/2026 +0 days VulDB entry created
04/09/2026 +1 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Status: Confirmed

CVE: CVE-2026-34721 (🔒)
GCVE (CVE): GCVE-0-2026-34721
GCVE (VulDB): GCVE-100-356333
CERT Bund: WID-SEC-2026-1000 - Zammad: Mehrere Schwachstellen

Entryinfo

Created: 04/08/2026 20:51
Updated: 04/09/2026 09:57
Changes: 04/08/2026 20:51 (66), 04/09/2026 09:57 (7)
Complete: 🔍
Cache ID: 216:1BE:103

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