PT-2026-31415 · Zammad · Zammad

CVE-2026-34718 · Published 2026-04-08 · Updated 2026-04-09

Positive Technologies (AI Summary)

CVSS v3.1

6.1

Medium

Base vector

AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N

Name of the Vulnerable Software and Affected Versions Zammad versions prior to 7.0.1 and prior to 6.5.4

Description Zammad, a web-based open-source helpdesk system, had an issue in its HTML sanitizer for ticket articles. The sanitizer lacked proper sanitization of URI schemes, allowing malicious content to be stored in the Zammad instance's database. While the Zammad GUI renders this content, the Content Security Policy (CSP) rules prevented harm from actions like clicking malicious links.

Recommendations Update to Zammad version 7.0.1 or later. Update to Zammad version 6.5.4 or later.

Exploit

Fix

XSS

Weakness Enumeration

CWE-80

Related Identifiers

CVE-2026-34718

GHSA-C2CF-9FC7-JHF3

Affected Products

Zammad

References · 6

• 🔥 https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/34xxx/CVE-2026-34718.json · Exploit
• https://github.com/zammad/zammad/security/advisories/GHSA-c2cf-9fc7-jhf3 · Vendor Advisory
• https://osv.dev/vulnerability/CVE-2026-34718 · Vendor Advisory
• https://nvd.nist.gov/vuln/detail/CVE-2026-34718 · Security Note
• https://twitter.com/VulmonFeeds/status/2042067659903082657 · Twitter Post
• https://twitter.com/CVEnew/status/2041975606259106111 · Twitter Post