CVE-2025-26858

High

Published: 01 December 2025

Published

01 December 2025

Modified

05 December 2025

KEV Added

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Patch

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CVSS Score 8.6 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

EPSS Score 0.0009 26.2th percentile

Risk Priority 17 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2025-26858 is a high-severity Improper Input Validation (CWE-20) vulnerability in Socomec Diris M-70 Firmware. Its CVSS base score is 8.6 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Application or System Exploitation (T1499.004); ranked at the 26.2th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified are NIST 800-53 SC-5 (Denial-of-service Protection) and SC-7 (Boundary Protection).

Threat & Defense at a Glance

What attackers do: exploitation maps to Application or System Exploitation (T1499.004). What defenders deploy: see the NIST 800-53 controls recommended below.

Threat & Defense Details

Mitigating Controls (NIST 800-53 r5)AI

SI-10 Information Input Validation good match

prevent

Directly addresses the CWE-20 improper input validation that enables specially crafted Modbus TCP packets to trigger the buffer overflow.

SC-5 Denial-of-service Protection good match

preventdetect

Limits the effects of denial-of-service attacks caused by the buffer overflow vulnerability through dedicated DoS protections.

SC-7 Boundary Protection good match

prevent

Controls external network communications at system boundaries to restrict unauthenticated access to the vulnerable Modbus TCP service.

MITRE ATT&CK Enterprise TechniquesAI

T1499.004 Application or System Exploitation Impact

Adversaries may exploit software vulnerabilities that can cause an application or system to crash and deny availability to users.

attack.mitre.org →

Why these techniques?

Buffer overflow in Modbus TCP service enables unauthenticated remote denial of service via application exploitation.

Confidence: HIGH · MITRE ATT&CK Enterprise v19.0

NVD Description

A buffer overflow vulnerability exists in the Modbus TCP functionality of Socomec DIRIS Digiware M-70 1.6.9. A specially crafted set of network packets can lead to denial of service. An attacker can send a sequence of unauthenticated packets to trigger…

this vulnerability.

Deeper analysisAI

CVE-2025-26858 is a buffer overflow vulnerability in the Modbus TCP functionality of Socomec DIRIS Digiware M-70 version 1.6.9. A specially crafted set of network packets can trigger the issue, leading to denial of service. The vulnerability is categorized under CWE-20 (Improper Input Validation) and carries a CVSS v3.1 base score of 8.6 (AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H).

An attacker with network access can exploit this vulnerability by sending a sequence of unauthenticated packets, requiring no privileges, user interaction, or special conditions beyond low-complexity network reachability. Successful exploitation results in high-impact denial of service due to the changed scope, disrupting availability without affecting confidentiality or integrity.

Advisories providing further details, including potential mitigations, are available from Talos Intelligence at https://talosintelligence.com/vulnerability_reports/TALOS-2025-2152 and from Socomec at https://www.socomec.fr/sites/default/files/2025-10/CVE-2025-26858---Diris-Digiware-Mxx-Dxx-_VULNERABILITIES_2025-10-01-16-38-44_English_0.pdf.