Vulnerability in Zimbra (CVE-2020-11737)

Summary

Vulnerability in Zimbra (CVE-2020-11737). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 9.0.0 or later.

Original description

The description as published by the source.

A cross-site scripting (XSS) vulnerability in Web Client in Zimbra 9.0 allows a remote attacker to craft links in an E-Mail message or calendar invite to execute arbitrary JavaScript. The attack requires an A element containing an href attribute with a "www" substring (including the quotes) followed immediately by a DOM event listener such as onmouseover. This is fixed in 9.0.0 Patch 2.

Source: OSV.dev (Open Source Vulnerabilities) NVD OSV

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-2020-11737 has been found in Zimbra.
Risk of unauthorized operations or information disclosure.
What to do: upgrade Zimbra to 9.0.0 or later.
If unsure, ask your IT team or search "Zimbra CVE-2020-11737" on the vendor's site.

CVE-2020-11737 (Zimbra)
Attack vector: remote (network-reachable) / unauthenticated
Patched: 9.0.0 — 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.

❓ What is the problem

A vulnerability (unclassified) exists in Zimbra.

📍 Affected scope

Check the vendor advisory for the affected versions of Zimbra.

🔥 Severity

Severity: ?. Risk of unauthorized operations or information disclosure.

🔧 How to fix

Update to 9.0.0.

🛡️ Workaround

Until the patch is applied: disable the affected feature, apply WAF rules, or restrict access via network ACLs.

🔍 Detection

Search webserver/proxy logs for unusual request patterns matching this CVE's known IOCs. Run grep -r 'Zimbra' . 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

1
Identify exposure identify
```
grep -r 'Zimbra' . | 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 Zimbra を grep し、稼働しているサービス・バージョンを把握する。
2
Apply patch patch
```
Upgrade Zimbra to 9.0.0
```
ステージング環境で 9.0.0 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。
3
Post-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。

References

advisory blog.zimbra.com
advisory wiki.zimbra.com
advisory wiki.zimbra.com