What is CVE-2023-22915?

CVE-2023-22915 is a high-severity vulnerability in Zyxel Usg 20w-Vpn, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2023-04-24.

How severe is CVE-2023-22915?

High severity. CVSS v3 base score is 7.5 out of 10.

Buffer overflow in Zyxel Usg 20w-Vpn

CVE-2023-22915

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.

Vulnerability class: Buffer Overflow

EPSS: 0.011 (62.1th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H.

Affected products

Zyxel Usg_20w-vpn
Zyxel Usg_20w-vpn_firmware
Zyxel Usg20(w)-vpn Firmware — versions 4.30 through 5.35
Zyxel Usg_flex_100
Zyxel Usg_flex_100_firmware
Zyxel Usg_flex_100w
Zyxel Usg_flex_100w_firmware
Zyxel Usg_flex_200
Zyxel Usg_flex_200_firmware
Zyxel Usg_flex_50

Weakness classification (CWE)

CWE-120 — Buffer Copy without Checking Size of Input (Classic Buffer Overflow)

References

security@zyxel.com.tw (Vendor Advisory)

Frequently asked questions

What is CVE-2023-22915?: CVE-2023-22915 is a high-severity vulnerability in Zyxel Usg 20w-Vpn, classified under Buffer Copy without Checking Size of Input (Classic Buffer Overflow). CVSS score: 7.5/10. Published 2023-04-24.
How severe is CVE-2023-22915?: High severity. CVSS v3 base score is 7.5 out of 10.