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800xa SystemApplication · Abb

CVE-2020-8479

CRITICAL · 9.8 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 →
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
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. an XML External Entity Injection vulnerability exists that allows an attacker to read or call arbitrary files from the license server and/or from the network and also block the license handling.

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 critical XML External Entity Injection (XXE) vulnerability in the Central Licensing Server component of multiple ABB industrial control products allows authenticated or unauthenticated attackers to read arbitrary files from the server file system, access arbitrary network resources, and cause denial of service by blocking license handling.

MitigationDisable XML external entity processing in the licensing server's XML parser configuration, implement strict input validation for XML submissions, and apply vendor-supplied patches or upgrades to the affected product versions.

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= 6.1
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
High
Integrity
High
Availability
High

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

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
    Locate the ABB product installed on the system (800xa System, Compact Hmi, or Control Builder Safe) and determine its exact version number from the application or system information
    Affected if The installed version matches one of the affected versions: 800xa System 5.1, 6.0, 6.0.1, 6.0.3, or 6.1; Compact Hmi 5.1, 6.0.1-1, or 6.0.3-2; Control Builder Safe 1.0, 1.1, or 2.0
  2. Verify Central Licensing Server component is present
    Check if the Central Licensing Server component is installed and running on the system, typically as a Windows service or application module associated with the ABB product
    Affected if The Central Licensing Server component is installed and active on the system
  3. Confirm XML processing is enabled for licensing
    Inspect the licensing server configuration to determine if XML parsing is enabled and capable of processing external entities
    Affected if XML processing is enabled in the licensing server configuration, allowing the vulnerability to be exploited

The system is affected if an ABB product version from the affected list is installed AND the Central Licensing Server component is present with XML processing capabilities enabled.

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

Disable XML external entity processing in the licensing server's XML parser configuration, implement strict input validation for XML submissions, and apply vendor-supplied patches or upgrades to the affected product versions.

Fix this in 800xa System Scoped from the published advisory
  • Consultation8.0 h
  • Implementation16.0 h
  • Testing12.0 h
  • Review / QA4.0 h
40.0 hours of engineering $7,000
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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-2020-8479 in production — separate from our analysis above.

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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
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