CVE-2026-41150 — mermaid
Fix: mermaid-js/mermaid@a59ea56CVE-2026-41150 is a CWE-835 vulnerability in mermaid. A fix is available for mermaid — see the affected versions and patch details below.
Mermaid Gantt Charts are vulnerable to an Infinite Loop DoS
Exploitation Status
Proof-of-concept exploit code exists
- CISA’s SSVC triage found public proof-of-concept exploit code for this CVE, though no confirmed active exploitation.
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-41150.
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
Real-World Exposure
How broadly this vulnerability is actually deployed: weekly install volume shows current usage, and reverse-dependency count shows how many other packages break if it stays unpatched.
mermaidnpmDescription
Impact
Mermaid v11.14.0 and earlier are vulnerable to a denial-of-service attack when rendering gantt charts, if they use the excludes attribute to exclude all dates.
Example:
gantt
excludes monday,tuesday,wednesday,thursday,friday,saturday,sunday
DoS :2025-01-01, 1d
mermaid.parse is unaffected, unless you then call the ganttDb.getTasks() (which is called when rendering a diagram).
Patches
This has been patched in:
- v11.15.0 (see faafb5d49106dd32c367f3882505f2dd625aa30e)
- v10.9.6 (see a59ea56174712ee5430dfd5bc877cb5151f501a6)
Workarounds
There are no workarounds available without updating to a newer version of mermaid.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | mermaid | ≥ 11.0.0-alpha.1&&< 11.15.0 | 11.15.0npm install mermaid@11.15.0 |
| 📦npm | mermaid | all versions | 10.9.6npm install mermaid@10.9.6 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for mermaid, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update mermaid to 11.15.0 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-41150 is resolved across your whole dependency graph.
Workarounds
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2026-41150 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2026-41150. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2026-41150 in your dependencies?
O3 Security finds CVE-2026-41150 across npm dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.