Live Exposure Defense: From CVE to Confirmed Exposure in 12 Hours – See more

Back
New CVE Detected

CVE-2026-43945 – Pre-Auth RCE – FUXA SCADA/HMI versions 1.2.11 to 1.3.0

Be the first to know when new zero-days emerge:

Subscribe to Email Alerts
Subscribe to RSS Feed

Summary

CVE-2026-43945 is a pre-authentication remote code execution vulnerability in FUXA, an open-source web-based SCADA/HMI/Dashboard software developed by frangoteam. The flaw stems from a path confusion bug in the server’s authentication middleware, allowing an unauthenticated remote attacker to bypass all access controls and achieve full RCE as root — even when the platform is running in its most secure configuration (Secure Mode Enabled and Node-RED Secure Authentication Enabled). The vulnerability carries a CVSS 4.0 base score of 8.9 (HIGH) and affects FUXA versions 1.2.11 through 1.3.0, with a fix available in 1.3.1.

Technical details

  • Root cause: The authentication middleware evaluates the full request URL — including query parameters — using a substring match: url.includes('/socket.io'). Any request whose URL contains this string is unconditionally passed through without authentication checks, as the server treats it as a public WebSocket handshake.
  • Trigger condition: An attacker appends ?x=/socket.io to any protected administrative HTTP endpoint. The flawed substring check matches the injected query parameter, causing the middleware to skip all authentication enforcement for that request.
  • Attack vector: Exploitable entirely over the network via HTTP/HTTPS. No credentials, local access, or user interaction are required. The bypass succeeds regardless of whether Secure Mode or Node-RED Secure Authentication is enabled, negating the platform’s built-in hardening controls.
  • Impact: Full remote code execution as root on the host running FUXA, resulting in complete compromise of confidentiality, integrity, and availability. A proof-of-concept exploit is publicly available (CVSS 4.0 E:P).

Affected software

  • FUXA >= 1.2.11 and < 1.3.1 (all releases from 1.2.11 through 1.3.0 inclusive)

Severity

CVSS 4.0 Base Score: 8.9 (HIGH)
Vector: CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:P

Associated weaknesses: CWE-288 (Authentication Bypass Using an Alternate Path or Channel), CWE-94 (Code Injection), CWE-284 (Improper Access Control), CWE-863 (Incorrect Authorization).

Mitigation and recommended actions

  • Immediate: Upgrade to FUXA version 1.3.1, which resolves the bypass by replacing the vulnerable full-URL substring check with req.path-based evaluation that strips query parameters before applying authentication decisions.
  • If immediate patching is not possible: Restrict network access to all FUXA instances at the firewall or network perimeter. FUXA should never be directly exposed to the public internet; place it behind a VPN or strict network controls until the patch is applied.

IONIX Status

The IONIX research team is tracking ongoing exploitation attempts and recommends immediate patching. Potentially affected assets are outlined in this post.

References

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report

How IONIX’s External Exposure Management Platform Detects and Validates
Zero-Days to Shrink MTTR

1

Map your entire attack surface (continously)

IONIX uses multi-factor discovery methods, including DNS analysis, certificate mapping, metadata inspection, and more, to automatically map every internet-facing asset across your environment. This includes cloud instances, third-party platforms, shadow IT, and even forgotten infrastructure that traditional tools miss.

2

Monitor for new CVEs

Dozens of threat intel feeds using agentic technology are continuously analyzed to detect the appearance of proof-of-concept code, exploit kits, and indicators of active targeting. IONIX goes further by applying AI to proactively evaluate whether emerging vulnerabilities are likely to be exploited, even before PoCs go public.

3

Identify Potential External Exposures

Not all CVEs matter. IONIX filters vulnerabilities by asking attacker-centric questions: Can it be reached from the internet? Does it require authentication? Is it being exploited in the wild? This dramatically reduces noise and focuses teams on threats that can actually be weaponized.

4

Create Safe, Scalable Exploit Validations

IONIX transforms real-world PoCs into safe, non-intrusive test payloads that can be run in production environments without disruption. These simulations are precisely targeted to the systems that are vulnerable, ensuring rapid validation without unnecessary load.

5

Execute Exploit Validations

By combining context about software stack, versioning, exposure status, and reachability, IONIX ensures that only the right payloads are executed against the right assets, maximizing efficiency and minimizing risk.

6

Drive Fast and Actionable Remediation

Results are routed through integrations with ticketing, SOAR, and SIEM tools. Issues are written in plain language, bundled into remediation clusters, and prioritized based on asset criticality, exploitability, and blast radius. This shortens mean time to remediation (MTTR) and empowers teams to act with confidence.

Are you exposed?

Get a free report of your organization’s exposure to this CVE and threat

  • Mapping of all Assets with this Technology
  • Identification of potentially exposed assets to this CVE
  • Confirmation of verified exploitable assets
Get Exposure Report
Close

Subscribe to Threat Center RSS

Copy/paste the link below into your preferred RSS reader or follow these instructions to subscribe to Slack alerts.

Open RSS feedSlack setup instructions

Close

Get Real-Time CVE Alerts to Your Email

Be the first to know when new zero-days emerge