Authentication Bypass in Symphony Plus

published 2020-12-22 5y ago modified 2026-06-17 4mo ago also EUVD-2020-17397

cvss: 9.8; version 3.1, CNA
cisa kev: Not listed; not in CISA's catalog
epss: 1.5%; EPSS 1.5% chance of exploitation in 30 days, percentile 74%
public exploits: 0; none known

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.

Patch / fix

fixed in 1

ABB ABB Ability™ Symphony® Plus Operations 2.1 SP1

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Exploit prediction

1.48% chance of exploitation in the next 30 days, higher than 74% of all scored CVEs (FIRST EPSS, 2026-11-09).

CVSS scores

assigned by	version	score	vector
CNA	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	3.1	9.8	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
NVD	2.0	7.5	AV:N/AC:L/Au:N/C:P/I:P/A:P

Affected products

ABB ABB Ability™ Symphony® Plus Operations

Classification

Weakness

CWE-602 Client-Side Enforcement of Server-Side Security
CWE-305 Authentication Bypass by Primary Weakness
CWE-669 Incorrect Resource Transfer Between Spheres

References

search.abb.com /library/Download.aspx?DocumentID=2PAA123980&LanguageCode=en&DocumentPartId=&Action=Launch
mitigation, vendor-advisory

Sources

CVE List CVE-2020-24683
NVD CVE-2020-24683

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