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CVE-2023-27990

Published: Apr 24, 2023Updated: Feb 25, 2026 Sources: CVE List NVD BDUCWE-79
4.8MEDIUM
NVD MITRE
EPSS Score
0.3%
Top 73.7%
CISA KEV
Not in KEV
Exploits
No Known Exploits
Remediation
Patch Available
Self-Check
OpenVAS

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.

No summary for this CVE yet.

CVSS Vector Breakdown

AV:NAC:LPR:HUI:RS:CC:LI:LA:N
Exploitability
AV:NAttack Vector
Network
AC:LAttack Complexity
Low
PR:HPrivileges Required
High
UI:RUser Interaction
Required
Scope
S:CScope
Changed
Impact
C:LConfidentiality
Low
I:LIntegrity
Low
A:NAvailability
None
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Weaknesses

CWE-79

Affected Products

Zyxel Communications Corp.
commercial·TWaka Zyxel
ATP200
Networking Infrastructure
ATP100
Networking Infrastructure
ATP700
Networking Infrastructure
ATP500
Networking Infrastructure
ATP100W
Networking Infrastructure
ATP800
Networking Infrastructure
USG FLEX 100
Networking Infrastructure
USG FLEX 50
Networking Infrastructure
and 35 more affected products View all →

Exploitability

Official Patch Available
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Attack Graph

Products CVE Techniques Tactics

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MITRE ATT&CK

2 techniques
Execution
Initial Access
View detailed technique mapping

References

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

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