PT-2026-32485 · Abb · Ac800M+3

Published 2026-04-13 · Updated 2026-05-19 · CVE-2025-3756

Positive Technologies (AI Summary)

CVSS v3.1

6.5

Medium

Base vector

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

Name of the Vulnerable Software and Affected Versions AC800M (System 800xA) versions 6.0.0x through 6.0.0303.0 AC800M (System 800xA) versions 6.1.0x through 6.1.0031.0 AC800M (System 800xA) versions 6.1.1x through 6.1.1202.0 AC800M (System 800xA) versions 6.2.0x through 6.2.0006.0 Symphony Plus SD Series versions A 0, A 1, A 2.003, A 3.005, A 4.001, B 0.005 Symphony Plus MR (Melody Rack) versions 3.10 through 3.52 S+ Operations versions 2.1, 2.2, 2.3, 3.3

Description An issue exists in the command handling of the IEC 61850 communication stack. An attacker with access to IEC 61850 networks can send a specially crafted 61850 packet to force the communication interfaces of PM 877, CI850, and CI868 modules into fault mode or cause the unavailability of S+ Operations 61850 connectivity. This results in a denial-of-service situation, disrupting industrial operations and power grids. This issue specifically impacts the 61850 communication function and does not affect the overall availability and functionality of the S+ Operations node.

Recommendations At the moment, there is no information about a newer version that contains a fix for this vulnerability. Implement network segmentation to contain attacks within isolated zones.

DoS

Weakness Enumeration

CWE-1284

Related Identifiers

CVE-2025-3756

Affected Products

Ac800M

S+ Operations

Symphony Plus

Symphony Plus Sd Series

References · 5

• https://nvd.nist.gov/vuln/detail/CVE-2025-3756 · Security Note
• https://twitter.com/windowsforum/status/2049885737609277875 · Twitter Post
• https://search.abb.com/library/Download.aspx?DocumentID=7PAA020125&LanguageCode=en&DocumentPartId=&Action=Launch · Note
• https://t.me/cveNotify/164015 · Telegram Post
• https://twitter.com/aviatrixtrc/status/2049903311944368371 · Twitter Post