Cross-Site Request Forgery (CSRF) in Zammad (CVE-2026-34721)
Summary
Vulnerability in Zammad (CVE-2026-34721). Confidential information can be exposed externally. Mitigation: upgrade to 7.0.1 or later.
Original description
The description as published by the source.
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.
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-2026-34721 has been found in Zammad.
Confidential information can be exposed externally. CVSS score: 6.5/10.
What to do: upgrade Zammad to 7.0.1 or later.
If unsure, ask your IT team or search "Zammad CVE-2026-34721" on the vendor's site.
CVE-2026-34721 (Zammad) — CWE-352 / CVSS v3 6.5
Attack vector: remote (network-reachable) / unauthenticated
Patched: 7.0.1 — apply immediately
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.
CSRF (CWE-352) exists in Zammad.
Check the vendor advisory for the affected versions of Zammad.
Severity: Medium (CVSS 6.5/10). Confidential information can be exposed externally.
Update to 7.0.1.
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
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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。 -
2Apply patch patch
Upgrade Zammad to 7.0.1ステージング環境で 7.0.1 に上げて回帰テスト → 本番反映。回帰テストはアプリの主要ハッピーパスを含めること。
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3Post-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。