Cyber Resilience

CVE-2023-28770

HighPublic PoC

Published: 27 April 2023

Published
27 April 2023
Modified
31 January 2025
KEV Added
Patch
CVSS Score v3.1 7.5 CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
EPSS Score 0.8485 99.4th percentile
Risk Priority 66 60% EPSS · 20% KEV · 20% CVSS

Summary

CVE-2023-28770 is a high-severity Exposure of Sensitive Information to an Unauthorized Actor (CWE-200) vulnerability in Zyxel Dx5401-B0 Firmware. Its CVSS base score is 7.5 (High).

Operationally, ranked in the top 0.6% of CVEs by exploit likelihood; it is not currently listed in the CISA KEV catalog; a public proof-of-concept is referenced.

Deeper analysis

CVE-2023-28770 is a sensitive information exposure vulnerability affecting the CGI “Export_Log” handler and the “zcmd” binary in Zyxel DX5401-B0 firmware versions prior to V5.17(ABYO.1)C0. The flaw permits an unauthenticated remote attacker to read arbitrary system files and extract the supervisor account password from an encrypted file, corresponding to CWE-200 and carrying a CVSS 3.1 base score of 7.5.

An attacker with network access can directly invoke the affected CGI endpoint or binary without credentials or user interaction, resulting in disclosure of configuration data and privileged credentials that can be used for further access.

Zyxel’s security advisory directs customers to upgrade DX5401-B0 devices to firmware V5.17(ABYO.1)C0 or later, which removes the exposure in the Export_Log CGI and zcmd components.

Public exploit material on PacketStorm describes the issue as one link in a chained remote-code-execution sequence against the same device family, and the CVE’s EPSS score has remained at its observed peak of 0.8485 since disclosure.

EU & UK References

Vulnerability details

The sensitive information exposure vulnerability in the CGI “Export_Log” and the binary “zcmd” in Zyxel DX5401-B0 firmware versions prior to V5.17(ABYO.1)C0 could allow a remote unauthenticated attacker to read the system files and to retrieve the password of the supervisor…

more

from the encrypted file.

CWE(s)

Related Threats

No named actor attribution yet. ATT&CK technique mapping in progress for this CVE.

Affected Assets

zyxel
dx5401-b0 firmware
≤ 5.17\(abyo.1\)c0

Mitigating Controls

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.

addresses: CWE-200 CWE-203

Concealment techniques directly prevent real sensitive data from being exposed to adversaries.

addresses: CWE-200 CWE-203

Restricts error message visibility to authorized recipients, directly reducing unauthorized exposure of sensitive information.

addresses: CWE-200

Automated marking applies security attributes to system outputs, making it harder for attackers to exploit unmarked sensitive information leading to unauthorized exposure.

addresses: CWE-200

Proper attribute retention and permitted-value enforcement limits unauthorized actors from accessing sensitive information lacking correct labels.

addresses: CWE-200

Prevents unauthorized exposure of sensitive information by prohibiting untrusted external systems from processing or storing it.

addresses: CWE-200

By enforcing authorization matching prior to sharing, the control reduces the risk of exposing sensitive information to unauthorized actors.

addresses: CWE-200

Review and removal of nonpublic information from publicly accessible systems directly prevents exposure of sensitive data to unauthorized actors.

addresses: CWE-200

Data mining protection mechanisms detect and block unauthorized bulk extraction of sensitive data, directly mitigating exposure to unauthorized actors.

References