CVE-2025-3756 - CVE House
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Status published High CVE-2025-3756

Denial of Service Vulnerabilities in System 800xA, Symphony® Plus IEC 61850

Vulnerability Description

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.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

The following person or organization is credited with identifying this vulnerability, as recorded in the NVD database:

  • ABB thanks Hitachi Energy for sharing the information affecting a commonly used software component.

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Affected Vendor

Affected Software

AC800M (System 800xA), Symphony Plus SD Series, Symphony Plus MR (Melody Rack), S+ Operations
Vulnerable Versions:
6.0.0x, 6.1.0x, 6.1.1x, 6.2.0x, A_0, A_1, A_2.003, A_3.005, A_4.001, B_0.005, 3.10, 2.1, 2.2, 2.3, 3.3

Timeline

Official Publish: April 13th, 2026
Last Modified: April 13th, 2026
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

Weaknesses (CWE)

CWE-1284

MITRE ATT&CK TTPs

No associated TTPs found for this vulnerability.