CVE-2026-43947
Fix: frangoteam/FUXA@78534daCVE-2026-43947 is a CWE-863 vulnerability in fuxa-server. O3 Security confirms whether CVE-2026-43947 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
FUXA Vulnerable to Unauthenticated Remote Code Execution via Script Test Mode Authorization Bypass
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.
- A successful exploit gives an attacker total control of the affected component, not partial access.
Exploitation and automatability from CISA’s SSVC triage for CVE-2026-43947.
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, a proxy for how much of the ecosystem is exposed.
fuxa-servernpmDescription
FUXA is a web-based Process Visualization (SCADA/HMI/Dashboard) software. Version 1.3.0 has an unauthenticated Remote Code Execution vulnerability when secureEnabled is set to true. The POST /api/runscript endpoint checks authorization against the stored script's permission by ID, but when test: true is set in the request, it compiles and executes attacker-supplied code instead of the stored script's code. An unauthenticated attacker who knows a valid script ID and name may execute arbitrary code via test mode if at least one server-side script exists and is accessible without restrictive permissions. Script IDs and names can be obtained through the unauthenticated information disclosure in GET /api/project (reported separately). The only prerequisite is that at least one server-side script exists in the project. Version 1.3.1 fixes the issue.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 📦npm | fuxa-server | ≥ 1.3.0&&< 1.3.1 | 1.3.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for fuxa-server. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update fuxa-server to 1.3.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2026-43947 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 pinpoints whether CVE-2026-43947 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2026-43947. 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-2026-43947 in your dependencies?
O3 detects CVE-2026-43947 across npm dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.