ABB S+ Operations — kwetsbaarheid CVE-2025-3756

A vulnerability exists in the command handling of the IEC 61850 communication stack included in the product revisions listed as affected in this CVE. An attacker with access to IEC 61850 networks could exploit the vulnera bility by using a specially crafted 61850 packet, forcing the communication interfaces of the PM 877, CI850 and CI868 modules into fault mode or causing unavailability of the S+ Operations 61850 connectivity, resulting in a denial-of-service situation.  The System 800xA IEC61850 Connect is not affected. Note: This vulnerability does not impact on the overall availability and functionality of the S+ Operations node, only the 61850 communication function.     This issue affects AC800M (System 800xA): from 6.0.0x through 6.0.0303.0, from 6.1.0x through 6.1.0031.0, from 6.1.1x through 6.1.1004.0, from 6.1.1x through 6.1.1202.0, from 6.2.0x through 6.2.0006.0; Symphony Plus SD Series: A_0, A_1, A_2.003, A_3.005, A_4.001, B_0.005; Symphony Plus MR (Melody Rack): from 3.10 through 3.52; S+ Operations: 2.1, 2.2, 2.3, 3.3.

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

ABB advises all customers to review their installations to determine if they are using an impacted product as listed above, no further analysis or tools are needed to make this determination. The recommended immediate actions per product are listed below: - CI868 (for AC 800M) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in 6.1.1 and 7.0 tracks for 800xA. AC 800M 6.1.1-3 is planned for Q2 2027, AC 800M 7.0 has been released in December 2025. - CI850 (for Symphony Plus SD Series) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in version C_0 or later (planned Q2 2026). - PM 877 (Symphony Plus MR) Devices with firmware versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected with firmware version 3.53 or later (planned Q1 2026). - S+ Operations Versions reported in Affected products are vulnerable. All the vulnerabilities will be corrected in version 3.4 or later (released in January 2026). ABB recommends customers apply updates, as they become available, at their earliest convenience. It is also advisable to review the Mitigating Factors, Workarounds and General security recommendations sections for additional actions which may help reduce overall risk.