CVE-2023-27991 - CVE House
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Status published High CVE-2023-27991

The post-authentication command injection vulnerability in the CLI command of...

Vulnerability Description

The post-authentication command injection vulnerability in the CLI command of Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow an authenticated attacker to execute some OS commands remotely.

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Affected Software

ATP series firmware, USG FLEX series firmware, USG FLEX 50(W) firmware, USG20(W)-VPN firmware, VPN series firmware
Vulnerable Versions:
4.32 through 5.35, 4.50 through 5.35, 4.16 through 5.35, 4.30 through 5.35

Timeline

Official Publish: April 24th, 2023
Last Modified: February 4th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

V3: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weaknesses (CWE)

CWE-78

MITRE ATT&CK TTPs

T1190 Exploit Public-Facing Application
Initial Access
T1059 Command and Scripting Interpreter
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1005 Data from Local System
Collection
T1041 Exfiltration Over C2 Channel
Exfiltration