Vulnerability in Zammad (CVE-2026-63206)
Summary
Vulnerability in Zammad (CVE-2026-63206). Risk of unauthorized operations or information disclosure.
Original description
The description as published by the source.
Zammad is a web based open source helpdesk/customer support system. Prior to 7.1.2, zammad's HTML sanitizer, which blocks remote images in ticket articles and email views, can be bypassed using a shortened URL format that omits the double slash after the scheme (for example a shortened HTTP URL instead of a shortened HTTP URL). Modern browsers treat both forms as equivalent remote URLs. As a result, an attacker who sends a crafted email or ticket can cause the recipient's browser to silently load an image from an external server, revealing when and by whom the ticket was opened. Zammad's "remote content blocked" warning is not shown because the sanitizer does not recognize the shortened form as remote. This issue is fixed in version 7.1.2.
Source: NIST National Vulnerability Database NVD
Auto-generated summary
Assembled by SecPulse from the source data (CVSS, CWE, affected versions) using templates — no AI involved. Check the original description and references below for exact details.
A vulnerability tracked as CVE-2026-63206 has been found in Zammad.
Risk of unauthorized operations or information disclosure.
What to do: apply the vendor's official patched release.
If unsure, ask your IT team or search "Zammad CVE-2026-63206" on the vendor's site.
CVE-2026-63206 (Zammad) — CWE-20
Plan: 1) Audit SBOM/dependencies, 2) Stage→prod upgrade, 3) Add WAF/proxy monitoring on affected endpoints, 4) Hunt IOCs in logs.
Refs: see the GHSA / vendor advisory / patched release linked on this page.
A vulnerability (CWE-20) exists in Zammad.
Check the vendor advisory for the affected versions of Zammad.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to the patched release per vendor advisory.
Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.
Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Zammad' . against your dependency files (package-lock.json, requirements.txt, go.sum) to find affected services.
Response actions
Concrete steps and command examples for SOC/SRE teams to execute in order
-
1Identify exposure identify
grep -r 'Zammad' . | grep -v node_modulesリポジトリと本番環境の依存ファイル (package-lock.json / requirements.txt / go.sum / Gemfile.lock 等) で
Zammadを grep し、稼働しているサービス・バージョンを把握する。 -
2Post-deployment verification verify
Confirm patched version is live in productionパッチ適用後、ステージングで PoC または同等の悪用パターンを再現して脆弱性が閉じたことを確認。本番ではアクセスログ・WAF でアラート再発が無いか継続監視。