Incorrect AuthorizationWeakness · CWE-863

CVE-2024-5539

CRITICAL · 9.2 CVSS v4.0 Published 2025-11-27
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
100/100
Remediation priority · Urgent
Remotely reachable No privileges Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
The Access Control Bypass vulnerability found in ALC WebCTRL and Carrier i-Vu in versions up to and including 8.5 allows a malicious actor to bypass intended access restrictions and expose sensitive information via the web based building automation server.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

The Access Control Bypass vulnerability in ALC WebCTRL and Carrier i-Vu building automation systems (versions up to 8.5) allows unauthenticated or authenticated attackers to circumvent intended access restrictions and access sensitive information through the web-based interface.

MitigationUpgrade to a version beyond 8.5 that contains the security patch; until then, implement compensating controls such as network segmentation, strict firewall rules limiting access to authorized IPs, and enhanced monitoring of web interface access logs.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
None
Authentication
X
User interaction
None
Scope
X

CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:H/VI:N/VA:N/SC:H/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify the building automation system product
    Access the web interface or system documentation to determine if the installed system is ALC WebCTRL or Carrier i-Vu. Check the login page, system information page, or system header/footer for product identification.
    Affected if The system is ALC WebCTRL or Carrier i-Vu
  2. Determine the installed version
    Locate the version information in the web-based interface (typically found in About, System Info, or Help sections) or check the installed software package on the host system.
    Affected if The installed version is 8.5 or any version below 8.5
  3. Verify web interface accessibility
    Determine if the web interface is accessible from network segments outside the trusted building automation network. Check firewall rules, NAT configurations, or reverse proxy settings that expose the web interface.
    Affected if The web interface is accessible from untrusted or external network segments without proper access restrictions
  4. Review access control configuration
    Examine user accounts, roles, and permission settings within the WebCTRL or i-Vu administration panel to verify that access restrictions are properly enforced for all authenticated and unauthenticated access paths.
    Affected if Weak or misconfigured access controls exist that allow unauthorized access to sensitive information

If the system is ALC WebCTRL or Carrier i-Vu version 8.5 or below with an accessible web interface, the environment is affected by this access control bypass vulnerability.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade to a version beyond 8.5 that contains the security patch; until then, implement compensating controls such as network segmentation, strict firewall rules limiting access to authorized IPs, and enhanced monitoring of web interface access logs.

Have this fixed Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA8.0 h
44.0 hours of engineering $7,720
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $12,352.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2024-5539 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2024-5539 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data