dbcve.org
800xa SystemApplication · Abb

CVE-2020-8476

HIGH · 7.5 CVSS v3.1 Published 2020-04-29
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
84/100
Remediation priority · High
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
For the Central Licensing Server component used in ABB products ABB Ability™ System 800xA and related system extensions versions 5.1, 6.0 and 6.1, Compact HMI versions 5.1 and 6.0, Control Builder Safe 1.0, 1.1 and 2.0, Symphony Plus -S+ Operations 3.0 to 3.2 Symphony Plus -S+ Engineering 1.1 to 2.2, Composer Harmony 5.1, 6.0 and 6.1, Melody Composer 5.3, 6.1/6.2 and SPE for Melody 1.0SPx (Composer 6.3), Harmony OPC Server (HAOPC) Standalone 6.0, 6.1 and 7.0, ABB Ability™ System 800xA/ Advant® OCS Control Builder A 1.3 and 1.4, Advant® OCS AC100 OPC Server 5.1, 6.0 and 6.1, Composer CTK 6.1 and 6.2, AdvaBuild 3.7 SP1 and SP2, OPCServer for MOD 300 (non-800xA) 1.4, OPC Data Link 2.1 and 2.2, Knowledge Manager 8.0, 9.0 and 9.1, Manufacturing Operations Management 1812 and 1909, ABB AbilityTM SCADAvantage versions 5.1 to 5.6.5, a weakness in validation of input exists that allows an attacker to alter licenses assigned to the system nodes by sending specially crafted messages to the CLS web service.

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 · high confidence

A weakness in input validation exists in the Central Licensing Server (CLS) web service used by multiple ABB products. An attacker can send specially crafted messages to the CLS web service to alter licenses assigned to system nodes without proper authorization checks.

MitigationImplement proper input validation, authentication, and authorization checks on the CLS web service to ensure only legitimate requests can modify license assignments. Apply vendor patches for the affected ABB products.

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

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
800xa SystemApplication
Affected:= 5.1= 6.0= 6.0.1= 6.0.3= 6.0.3.3= 6.1
Compact HmiApplication
Affected:= 5.1= 6.0.1-1= 6.0.3-2
Control Builder SafeApplication
Affected:= 1.0= 1.1= 2.0

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
User interaction
None
Scope
Unchanged
Confidentiality
None
Integrity
High
Availability
None

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:N

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 installed ABB product and version
    Check system inventory or installed programs for ABB 800xA System, ABB Compact HMI, or ABB Control Builder Safe and note the exact version number
    Affected if The installed version matches 5.1, 6.0, 6.0.1, 6.0.3, 6.0.3.3, or 6.1 for 800xA; 5.1, 6.0.1-1, or 6.0.3-2 for Compact HMI; or 1.0, 1.1, or 2.0 for Control Builder Safe
  2. Locate Central Licensing Server (CLS) component
    Search for CLS or Central Licensing Server in installed services, applications, or program directories on the system
    Affected if CLS component is installed and present on the system alongside the affected ABB product
  3. Verify CLS web service status
    Check if the CLS web service is running and listening on network ports (typically web service ports 80/443 or configured CLS ports)
    Affected if The CLS web service is running and accessible on the network
  4. Inspect CLS web service authentication configuration
    Review the CLS web service configuration files or settings for authentication and authorization enforcement on license modification endpoints
    Affected if The CLS web service lacks proper authentication/authorization controls or allows unauthenticated license modification requests

The environment is affected if an affected ABB product (800xA, Compact HMI, or Control Builder Safe) is installed with the Central Licensing Server web service enabled and lacking proper authorization checks on license modification functions.

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

Implement proper input validation, authentication, and authorization checks on the CLS web service to ensure only legitimate requests can modify license assignments. Apply vendor patches for the affected ABB products.

Fix this in 800xa System Scoped from the published advisory
  • Consultation4.0 h
  • Implementation8.0 h
  • Testing4.0 h
  • Review / QA2.0 h
18.0 hours of engineering $3,200
Get help mitigating

An estimate, not a bill — we confirm scope with you before any work starts. Need it this week? Rush from $5,120.

Scan for this in your stack

Free · runs locally
dbcve dependency scanner

Check whether your project pulls in CVE-2020-8476 — or any other known-vulnerable package — straight from your lock files. Free and open source; it runs locally and uploads nothing.

Get it on GitHub Scan in the browser

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-2020-8476 in production — separate from our analysis above.

No notes yet

Be the first to add a field note for this CVE — a mitigation you’ve verified, a version caveat, or a link to a working fix. Sign in above to contribute.

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