Vulnerability in mermaid (CVE-2021-43861)
Summary
Vulnerability in mermaid (CVE-2021-43861). Risk of unauthorized operations or information disclosure. Mitigation: upgrade to 8.13.8 or later.
Original description
The description as published by the source.
Mermaid is a Javascript based diagramming and charting tool that uses Markdown-inspired text definitions and a renderer to create and modify complex diagrams. Prior to version 8.13.8, malicious diagrams can run javascript code at diagram readers' machines. Users should upgrade to version 8.13.8 to receive a patch. There are no known workarounds aside from upgrading.
Source: OSV.dev (Open Source Vulnerabilities) NVD GitHub Advisory 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-2021-43861 has been found in mermaid.
Risk of unauthorized operations or information disclosure.
What to do: upgrade mermaid to 8.13.8 or later.
If unsure, ask your IT team or search "mermaid CVE-2021-43861" on the vendor's site.
CVE-2021-43861 (mermaid) — CWE-20
Attack vector: remote (network-reachable)
Patched: 8.13.8 — 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.
A vulnerability (CWE-20) exists in mermaid.
Check the vendor advisory for the affected versions of mermaid.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 8.13.8.
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 'mermaid' . 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 'mermaid' . | 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
mermaid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 mermaid to 8.13.8ステージング環境で 8.13.8 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。
-
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。
Affected packages
Fix status by distribution
Fixed packages published by each distribution for this CVE
- Debian DEBIAN-CVE-2021-43861 node-mermaid Fixed in: 8.13.8+~cs10.4.16-1
- Ubuntu UBUNTU-CVE-2021-43861 node-mermaid
References
- advisory github.com
- advisory nvd.nist.gov
- advisory github.com
- package github.com
- patch github.com