Security Resilience

CVE-2023-31277

Piigab M-Bus 900S Firmware

Published
06 July 2023
Modified
21 November 2024
CVSS Score v3.1 7.5
Click a component to see what it means
Raw vectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.0057 46th percentile
Risk Priority 58 floored blend · peak EPSS

CVSS and EPSS are reproduced from their sources (NVD, FIRST EPSS). Risk Priority is our own derived reading, not an NVD score.

Summary

CVE-2023-31277 is a high-severity Unprotected Transport of Credentials (CWE-523) vulnerability in Piigab M-Bus 900S Firmware. Its CVSS base score is 7.5 (High).

Operationally, exploitation aligns with the MITRE ATT&CK technique Proc Filesystem (T1003.007); ranked at the 46th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic Failures

EU & UK References

Vulnerability Data

PiiGAB M-Bus transmits credentials in plaintext format.

CWE(s)
CWE-523

Related Threats

MITRE ATT&CK Enterprise Techniques

T1003.007 Proc Filesystem Credential Access
Adversaries may gather credentials from the proc filesystem or `/proc`.
attack.mitre.org →
T1003.008 /etc/passwd and /etc/shadow Credential Access
Adversaries may attempt to dump the contents of <code>/etc/passwd</code> and <code>/etc/shadow</code> to enable offline password cracking.
attack.mitre.org →
T1006 Direct Volume Access Stealth
Adversaries may directly access a volume to bypass file access controls and file system monitoring.
attack.mitre.org →
T1010 Application Window Discovery Discovery
Adversaries may attempt to get a listing of open application windows.
attack.mitre.org →
T1012 Query Registry Discovery
Adversaries may interact with the Windows Registry to gather information about the system, configuration, and installed software.
attack.mitre.org →
T1014 Rootkit Stealth
Adversaries may use rootkits to hide the presence of programs, files, network connections, services, drivers, and other system components.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-35120Same product: Piigab M-Bus 900S
CVE-2023-35987Same product: Piigab M-Bus 900S
CVE-2023-36859Same product: Piigab M-Bus 900S
CVE-2023-33868Same product: Piigab M-Bus 900S
CVE-2023-35765Same product: Piigab M-Bus 900S
CVE-2023-34433Same product: Piigab M-Bus 900S
CVE-2023-32652Same product: Piigab M-Bus 900S
CVE-2023-34995Same product: Piigab M-Bus 900S
CVE-2024-1509Shared CWE-523
CVE-2025-61121Shared CWE-523

Affected Assets

piigab
m-bus 900s firmware
all versions

Mitigating Controls

Control response

Prevent
Stop it (NIST 800-53)

—

Detect
Catch it (NIST detect / respond)

—

Harden
Shrink the surface (DISA STIG)
  • 5 hardening rules · 3 OS baselines
Validate
Prove the fix (OWASP ASVS)

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Likely Mitigating Controls AI

Per-CVE control mapping for this CVE has not run yet; the list below is derived from the weakness types (CWEs) cited in the NVD entry.

SC-37 Out-of-band Channels
addresses: CWE-523

Using a distinct channel for credential transmission prevents unprotected transport over the application's normal communication path.

SC-8 Transmission Confidentiality and Integrity
addresses: CWE-523

Requiring protected transport for credentials directly mitigates unprotected credential transmission over networks.

SC-9 Transmission Confidentiality
addresses: CWE-523

Prevents unprotected transport of credentials by mandating confidentiality mechanisms such as TLS for all sensitive data flows.

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-04 partial match
blocks

Protecting identity assertions in transit covers credential transport but is narrower than the full control scope.

PR.DS-02 partial match
blocks

Encryption of data-in-transit directly prevents exposure of credentials during login.

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.

A.5.14 Information transfer partial match
blocks

Requires secure information transfer, which can include protecting credentials in transit.

A.5.17 Authentication information partial match
degrades

Addresses management of authentication information, indirectly supporting protection during transmission.

A.8.19 Installation of software on operational systems partial match
removes
A.8.20 Networks security partial match
blocks

Requires network security controls that can protect credential transmission.

A.8.21 Security of network services partial match
blocks

A.8.21 mandates identifying/implementing network service security features including authentication, encryption, and connection controls plus rules on allowed networks, authentication requirements, and monitoring; this directly stops in-transit credential exposure for most network-based logins (e.g. via mandated TLS), with a bounded remainder of non-network or non-service-mediated credential flows.

A.8.24 Use of cryptography partial match
blocks

Requires use of cryptography, directly enabling encryption of credentials in transit.

Hardening callouts derived

Configuration rules from DISA STIG baselines that bear on weaknesses of the type cited by this CVE. Each rule is shown with the relationship its mapping actually records, against the CWE it was authored against. Derived via CVE→CWE over `controls_xwalks` (higher-evidence rows only; rows rated `none` are excluded).

RHEL 8 (2 rules)
  • V-230487 RHEL 8 must not have the telnet-server package installed. blocks CWE-523
  • V-230492 RHEL 8 must not have the rsh-server package installed. blocks CWE-523

References