CVE-2026-34719

HIGH EPSS 15.4%
Published Apr 8, 20262mo ago · Modified Jun 17, 20262w ago
8.3 CVSS 4.0
High
Find Similar
Published Apr 8, 2026 2mo ago
Last Modified Jun 17, 2026 2w ago

Description

Zammad is a web based open source helpdesk/customer support system. Prior to 7.0.1 and 6.5.4, the webhook model was missing a proper validation for loop back addresses, or link-local addresses — only the URL scheme (HTTP/HTTPS) as well as the hostname was checked. This could end up in retrieving confidential metadata of cloud/hosting providers. The existing check is now extended and is applied when configuring webhooks as well as triggering webhook jobs. This vulnerability is fixed in 7.0.1 and 6.5.4.

CVSS Details

Base Score
8.3
Exploitability
—
Impact
—
Vector string
CVSS:4.0/AV:N/AC:L/AT:N/PR:H/UI:N/VC:L/VI:N/VA:H/SC:L/SI:N/SA:H/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X
Attack Vector Network
Attack Complexity Low
Privileges Required High
User Interaction None
Scope X

Threat Intelligence

EPSS Exploit Probability
15.4% percentile
Exploit & Patch Status
No Known Exploit
No Patch Available

Weaknesses 1

CWE-918 Server-Side Request Forgery (SSRF) Validation

Affected Products 2

VendorProductVersionRange
zammadzammad* <6.5.4
zammadzammad7.0.0any

References 1

  • github.com https://github.com/zammad/zammad/security/advisories/GHSA-2vgc-vfh2-rw75
    Vendor Advisory

Remediation

No remediation data recorded yet

Check vendor advisories and the NVD entry for patch availability.