CVE-2023-27992 : The pre-authentication command injection vulnerability in the Zyxel NAS326 firmw

The pre-authentication command injection vulnerability in the Zyxel NAS326 firmware versions prior to V5.21(AAZF.14)C0, NAS540 firmware versions prior to V5.21(AATB.11)C0, and NAS542 firmware versions prior to V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands remotely by sending a crafted HTTP request.

Published 2023-06-19 12:15:09

Updated 2023-06-27 12:49:35

Source Zyxel Corporation

View at NVD, CVE.org

Products affected by CVE-2023-27992

Zyxel » Nas326 Firmware
Versions up to, including, (<=) 5.21\(aazf.13\)c0
cpe:2.3:o:zyxel:nas326_firmware:*:*:*:*:*:*:*:*
Matching versions
When used together with: Zyxel » Nas326 » Version: N/A
Zyxel » Nas540 Firmware
Versions up to, including, (<=) 5.21\(aatb.10\)c0
cpe:2.3:o:zyxel:nas540_firmware:*:*:*:*:*:*:*:*
Matching versions
When used together with: Zyxel » Nas540 » Version: N/A
Zyxel » Nas542 Firmware
Versions up to, including, (<=) 5.21\(abag.10\)c0
cpe:2.3:o:zyxel:nas542_firmware:*:*:*:*:*:*:*:*
Matching versions
When used together with: Zyxel » Nas542 » Version: N/A

CVE-2023-27992 is in the CISA Known Exploited Vulnerabilities Catalog

CISA vulnerability name:

Zyxel Multiple NAS Devices Command Injection Vulnerability

CISA required action:

Apply updates per vendor instructions.

CISA description:

Multiple Zyxel network-attached storage (NAS) devices contain a pre-authentication command injection vulnerability that could allow an unauthenticated attacker to execute commands remotely via a crafted HTTP request.

Notes:

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-pre-authentication-command-injection-vulnerability-in-nas-products; https://nvd.nist.gov/vuln/detail/CVE-2023-27992

Added on 2023-06-23 Action due date 2023-07-14

Exploit prediction scoring system (EPSS) score for CVE-2023-27992

EPSS FAQ

2.94%

Probability of exploitation activity in the next 30 days EPSS Score History

~ 91 %

Percentile, the proportion of vulnerabilities that are scored at or less

CVSS scores for CVE-2023-27992

Base Score	Base Severity	CVSS Vector	Exploitability Score	Impact Score	Score Source	First Seen
9.8	CRITICAL	CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H	3.9	5.9	Zyxel Corporation
Attack Vector: Network Attack Complexity: Low Privileges Required: None User Interaction: None Scope: Unchanged Confidentiality: High Integrity: High Availability: High

CWE ids for CVE-2023-27992

CWE-78 Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')

The product constructs all or part of an OS command using externally-influenced input from an upstream component, but it does not neutralize or incorrectly neutralizes special elements that could modify the intended OS command when it is sent to a downstream component.
Assigned by:
- nvd@nist.gov (Primary)
- security@zyxel.com.tw (Secondary)

References for CVE-2023-27992

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-pre-authentication-command-injection-vulnerability-in-nas-products

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