What’s Vulnerable › Vulnerabilities

CVE-2020-24683: Authentication Bypass in Symphony Plus

• Severity: critical (CVSS 9.8 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 1.5% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2020-12-22 · updated 2026-06-17
• Weakness: CWE-305

Description

The affected versions of S+ Operations (version 2.1 SP1 and earlier) used an approach for user authentication which relies on validation at the client node (client-side authentication). This is not as secure as having the server validate a client application before allowing a connection. Therefore, if the network communication or endpoints for these applications are not protected, unauthorized actors can bypass authentication and make unauthorized connections to the server application.

Affected products

• ABB Symphony + Historian: 3.0, 3.1
• ABB Symphony + Operations: 1.1, 2.0, 2.1-sp1, 2.1-sp2, 3.0, 3.1 (+2)

References

• https://search.abb.com/library/Download.aspx?DocumentID=2PAA123980&LanguageCode=en&DocumentPartId=&Action=Launch
• https://search.abb.com/library/Download.aspx?DocumentID=2PAA123980&LanguageCode=en&DocumentPartId=&Action=Launch

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