CVE-2023-27990

Description

The cross-site scripting (XSS) vulnerability in 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 with administrator privileges to store malicious scripts in a vulnerable device. A successful XSS attack could then result in the stored malicious scripts being executed when the user visits the Logs page of the GUI on the device.

Category

4.8
CVSS
Severity: Medium
CVSS 3.1 •
EPSS 0.15%
Vendor Advisory zyxel.com
Affected: Zyxel ATP series firmware
Affected: Zyxel USG FLEX series firmware
Affected: Zyxel USG FLEX 50(W) firmware
Affected: Zyxel USG20(W)-VPN firmware
Affected: Zyxel VPN series firmware
Published at:
Updated at:

References

Link Tags
https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls vendor advisory

Frequently Asked Questions

What is the severity of CVE-2023-27990?
CVE-2023-27990 has been scored as a medium severity vulnerability.
How to fix CVE-2023-27990?
To fix CVE-2023-27990, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2023-27990 being actively exploited in the wild?
As for now, there are no information to confirm that CVE-2023-27990 is being actively exploited. According to its EPSS score, there is a ~0% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
What software or system is affected by CVE-2023-27990?
CVE-2023-27990 affects Zyxel ATP series firmware, Zyxel USG FLEX series firmware, Zyxel USG FLEX 50(W) firmware, Zyxel USG20(W)-VPN firmware, Zyxel VPN series firmware.
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