Cyber Resilience

CVE-2023-40544

Westermo L206-F2G Firmware 4.24

Published
06 February 2024
Modified
21 November 2024
CVSS Score v3.1 5.7
Click a component to see what it means
Raw vectorCVSS:3.1/AV:A/AC:L/PR:N/UI:R/S:U/C:H/I:N/A:N
EPSS Score 0.0017 6th percentile
Risk Priority 42 floored blend · peak EPSS

Summary

CVE-2023-40544 is a medium-severity Cleartext Transmission of Sensitive Information (CWE-319) vulnerability in Westermo L206-F2G Firmware. Its CVSS base score is 5.7 (Medium).

Operationally, exploitation aligns with the MITRE ATT&CK technique Network Sniffing (T1040); ranked at the 6th 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 SC-8 (Transmission Confidentiality and Integrity) — see the control section below for these in your framework.

OWASP Top 10 for Web (2025)

A04:2025 Cryptographic Failures

EU & UK References

Vulnerability Data

An attacker with access to the network where the affected devices are located could maliciously actions to obtain, via a sniffer, sensitive information exchanged via TCP communications.

CWE(s)
CWE-319

Related Threats

MITRE ATT&CK Enterprise Techniques

T1040 Network Sniffing Credential Access
Adversaries may passively sniff network traffic to capture information about an environment, including authentication material passed over the network.
attack.mitre.org →
Derived from this CVE’s CWE(s) via the direct CWE→ATT&CK cross-walk.

CVEs Like This One

CVE-2023-42765Same product: Westermo L206-F2G
CVE-2023-38579Same product: Westermo L206-F2G
CVE-2023-45213Same product: Westermo L206-F2G
CVE-2023-40143Same product: Westermo L206-F2G
CVE-2023-45222Same product: Westermo L206-F2G
CVE-2024-37183Same vendor: Westermo
CVE-2023-45735Same product: Westermo L206-F2G
CVE-2023-45227Same product: Westermo L206-F2G
CVE-2025-62330Shared CWE-319
CVE-2025-0432Shared CWE-319

Affected Assets

westermo
l206-f2g firmware
4.24

Mitigating Controls

Mitigating Controls (NIST 800-53 r5) AI

SC-8 Transmission Confidentiality and Integrity good match

SC-8 directly requires protecting confidentiality of transmitted information, which structurally eliminates cleartext transmission of sensitive data.

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.DS-02 full match
prevents

Encryption of data-in-transit directly prevents cleartext transmission while the control also addresses integrity and availability.

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.8.21 Security of network services mostly match
prevents

Specifying encryption and other security technology for network services prevents transmission of sensitive information in cleartext over potentially untrusted channels.

A.5.14 Information transfer partial match
prevents

Mandating cryptographic protection and stronger authentication on public networks stops the transmission of plaintext sensitive information.

A.6.7 Remote working partial match
mitigates

Specifying communications-security requirements and secure remote-access methods (including encryption expectations) prevents the transmission of sensitive data in cleartext over home or public networks.

A.7.12 Cabling security partial match
mitigates

Armoured conduits, electromagnetic shielding and locked enclosures make passive eavesdropping on unencrypted traffic traversing the cables more difficult, mitigating exposure of sensitive data in transit.

References