Vulnerability in mermaid (CVE-2026-71439)
Summary
Vulnerability in mermaid (CVE-2026-71439). Risk of unauthorized operations or information disclosure. Exploitable via ticks. Mitigation: upgrade to 11.16.1 or later.
Original description
The description as published by the source.
Impact
Mermaid radar diagrams allow arbitrary large values for ticks, which can cause high CPU usage, freezing the webpage/JavaScript process for long periods of time, until the process is eventually killed due to OOM/running out of memory.
Proof-of-concept
radar-beta
axis a, b
curve c {1, 1}
ticks 1000000000
Patches
Has the problem been patched? What versions should users upgrade to?
This problem has been patched by https://github.com/mermaid-js/mermaid/commit/59b22fad2b3bb04f87a476c84a8a2b24679e607e, which was released in Mermaid v11.16.1
Workarounds
Is there a way for users to fix or remediate the vulnerability without upgrading?
There are no known workarounds without updating to a patched version of mermaid.
References
Are there any links users can visit to find out more?
Source: GitHub Security Advisories (Global) NVD GitHub Advisory
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-2026-71439 has been found in mermaid.
Attackers can target a specific entry point like ticks over the network to misuse the product.
Risk of unauthorized operations or information disclosure.
What to do: upgrade mermaid to 11.16.1 or later.
If unsure, ask your IT team or search "mermaid CVE-2026-71439" on the vendor's site.
CVE-2026-71439 (mermaid) — CWE-606
Attack surface: ticks
Patched: 11.16.1 — 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.
A vulnerability (CWE-606) exists in mermaid. Attackers reach the vulnerable code path via ticks.
Check the vendor advisory for the affected versions of mermaid. Attack surface: ticks.
Severity: ?. Risk of unauthorized operations or information disclosure.
Update to 11.16.1.
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 '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
-
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 11.16.1ステージング環境で 11.16.1 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。
-
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-2026-71439 node-mermaid
- Ubuntu UBUNTU-CVE-2026-71439 node-mermaid