high
7.5
CWE
120 119
Advisory Published
Updated

CVE-2023-22915: Buffer Overflow

First published: Mon Apr 24 2023(Updated: )

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.

Credit: security@zyxel.com.tw

Affected SoftwareAffected VersionHow to fix
Zyxel USG Flex 100 firmware>=4.50<=5.35
Zyxel USG FLEX 100
Zyxel USG FLEX 100w firmware>=4.50<=5.35
Zyxel USG FLEX 100w firmware
Zyxel USG FLEX 200>=4.50<=5.35
Zyxel USG FLEX 200 firmware
Zyxel USG FLEX 50(W) series firmware>=4.50<=5.35
Zyxel USG FLEX 50
Zyxel USG FLEX 50w>=4.30<=5.35
Zyxel USG FLEX 50(W) series firmware
Zyxel USG FLEX 500>=4.50<=5.35
Zyxel USG FLEX 500 firmware
Zyxel USG FLEX firmware>=4.50<=5.35
Zyxel USG FLEX 700 firmware
Zyxel VPN100>=4.50<=5.35
Zyxel VPN100 Firmware
Zyxel VPN1000 Firmware>=4.50<=5.35
Zyxel VPN1000 Firmware
Zyxel Zywall VPN 300 Firmware>=4.50<=5.35
Zyxel Zywall VPN300
Zyxel Zywall VPN 50 Firmware>=4.50<=5.35
Zyxel VPN50 Firmware
Zyxel USG 20w-VPN Firmware>=4.30<=5.35
Zyxel USG20

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Reference Links

Frequently Asked Questions

  • What is the vulnerability ID of this Zyxel USG FLEX series firmware vulnerability?

    The vulnerability ID of this Zyxel USG FLEX series firmware vulnerability is CVE-2023-22915.

  • What is the severity of CVE-2023-22915?

    CVE-2023-22915 has a severity rating of 7.5 (High).

  • Which software versions are affected by CVE-2023-22915?

    CVE-2023-22915 affects 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.

  • How can I fix CVE-2023-22915?

    To fix CVE-2023-22915, it is recommended to update to the latest firmware version provided by Zyxel.

  • Where can I find more information about this vulnerability?

    You can find more information about CVE-2023-22915 on Zyxel's official website: https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-vulnerabilities-of-firewalls-and-aps

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