Cyber Resilience

CVE-2025-20085

Access Control in Socomec Diris M-70 Firmware 1.6.9

Published
01 December 2025
Modified
05 December 2025
Patch / advisory
CVSS Score v3.1 7.2
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:L/I:L/A:N
EPSS Score 0.0027 18th percentile
Risk Priority 55 floored blend · peak EPSS

Summary

CVE-2025-20085 is a high-severity Missing Authentication for Critical Function (CWE-306) vulnerability in Socomec Diris M-70 Firmware. Its CVSS base score is 7.2 (High).

Operationally, ranked at the 18th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

The strongest mitigations our analysis identified map to AC-3 (Access Enforcement) and IA-2 (Identification and Authentication (Organizational Users)) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

EU & UK References

Vulnerability Data

A denial of service vulnerability exists in the Modbus RTU over TCP functionality of Socomec DIRIS Digiware M-70 1.6.9. A specially crafted network packet can lead to denial of service and weaken credentials resulting in default documented credentials being applied…

more

to the device. An attacker can send an unauthenticated packet to trigger this vulnerability.

CWE(s)

Related Threats

CVEs Like This One

CVE-2025-23417Same product: Socomec Diris M-70
CVE-2024-49572Same product: Socomec Diris M-70
CVE-2025-54850Same product: Socomec Diris M-70
CVE-2025-55222Same product: Socomec Diris M-70
CVE-2025-54851Same product: Socomec Diris M-70
CVE-2024-48882Same product: Socomec Diris M-70
CVE-2025-55221Same product: Socomec Diris M-70
CVE-2024-53684Same product: Socomec Diris M-70
CVE-2024-48894Same product: Socomec Diris M-70
CVE-2025-26858Same product: Socomec Diris M-70

Affected Assets

socomec
diris m-70 firmware
1.6.9

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)
  • AC-3 Access Enforcement
  • IA-2 Identification and Authentication (Organizational Users)
  • SC-5 Denial-of-service Protection
Detect
Catch it (NIST detect / respond)

Harden
Shrink the surface (DISA STIG)
  • 6 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)
  • V6.2.3
  • V6.4.4
  • V10.4.16
  • V12.1.3

Mitigating Controls (NIST 800-53 r5) AI

prevent

Directly enforces authentication and access restrictions on the Modbus RTU over TCP interface, blocking the unauthenticated crafted packet that triggers DoS and credential reset.

prevent

Requires identification and authentication before any access to critical device functions, eliminating the missing-authentication flaw (CWE-306) that allows unauthenticated packets.

prevent

Implements denial-of-service protection mechanisms that can limit or throttle malformed Modbus traffic before it can crash the device or force default credentials.

Mitigating Controls (NIST CSF 2.0) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→CSF cross-walk (authority under review) — links open the control.

PR.AA-03 full match
prevents

Directly requires authentication of users/services/hardware, which eliminates missing authentication for critical functions.

PR.AA-01 partial match
prevents

Managing identities and credentials is a prerequisite for authentication but does not itself enforce it on critical functions.

PR.AA-05 partial match
prevents

Defining and enforcing authorizations assumes prior authentication and therefore only partially mitigates the absence of authentication.

PR.IR-01 partial match
prevents

Protecting networks from unauthorized access can be undermined by missing authentication but does not address the root authentication gap.

Mitigating Controls (ISO/IEC 27001:2022 Annex A) AI

Derived directly from the weakness types (CWEs) cited in the NVD entry via our AI-authored CWE→ISO cross-walk (authority under review) — links open the control.

prevents

The control explicitly calls for authentication before any critical function is reached, eliminating the possibility of bypassing authentication for high-value operations.

prevents

Mandating authentication requirements for critical functions at the requirements-gathering stage ensures that essential operations are not left unprotected by missing login or verification mechanisms.

mitigates

Mandating authentication for network services and critical functions stops attackers from invoking sensitive operations without credentials, closing gaps where authentication is absent for important capabilities.

prevents

Security engineering principles insist on authentication and authorization for every critical function, eliminating entry points that lack any access control mechanism.

none

Requiring strong authentication and access-privilege enablement for remote connections ensures that critical functions cannot be invoked without proper verification, closing a gap that would otherwise allow unauthenticated use.

none

Mandatory use of access cards, biometrics, or two-factor authentication ensures that critical physical areas cannot be entered without proper authentication.

References