CVE-2023-22915 - CVE House
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Status published High CVE-2023-22915

A buffer overflow vulnerability in the “fbwifi_forward.cgi” CGI program of...

Vulnerability Description

A buffer overflow vulnerability in the “fbwifi_forward.cgi” CGI program of Zyxel USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.30 through 5.35, USG20(W)-VPN firmware versions 4.30 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow a remote unauthenticated attacker to cause DoS conditions by sending a crafted HTTP request if the Facebook WiFi function were enabled on an affected device.

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

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

Timeline

Official Publish: April 24th, 2023
Last Modified: February 12th, 2025
Added to House: July 22nd, 2026

CVSS Vectors

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

Weaknesses (CWE)

CWE-120

MITRE ATT&CK TTPs

T1203 Exploitation for Client Execution
Execution
T1068 Exploitation for Privilege Escalation
Privilege Escalation
T1055 Process Injection
Defense Evasion
T1105 Ingress Tool Transfer
Command and Control