Usg1900 Firmware
CVE-2021-35029
CRITICAL
Severity by source
AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Primary rating from NVD · only source for this CVE.
CVSS VectorNVD
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Lifecycle Timeline
1DescriptionNVD
An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device.
AnalysisAI
An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35. Rated critical severity (CVSS 9.8), this vulnerability is remotely exploitable, no authentication required, low attack complexity. No vendor patch available.
Technical ContextAI
This vulnerability is classified as Improper Authentication (CWE-287), which allows attackers to bypass authentication mechanisms to gain unauthorized access. An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.64 and USG Flex, ATP, and VPN series firmware versions 4.35 through 5.01, which could allow a remote attacker to execute arbitrary commands on an affected device. Affected products include: Zyxel Usg1900 Firmware, Zyxel Usg1100 Firmware, Zyxel Usg310 Firmware, Zyxel Usg210 Firmware, Zyxel Usg110 Firmware. Version information: through 4.64.
RemediationAI
No vendor patch is available at time of analysis. Monitor vendor advisories for updates. Implement multi-factor authentication, enforce strong password policies, use proven authentication frameworks.
More in Usg1900 Firmware
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Missing Access Control in the "Free Time" component of several Zyxel UAG, USG, and ZyWall devices allows a remote attack
A reflective Cross-site scripting (XSS) vulnerability in the free_time_failed.cgi CGI program in selected Zyxel ZyWall,
On Zyxel ATP200, ATP500, ATP800, USG20-VPN, USG20W-VPN, USG40, USG40W, USG60, USG60W, USG110, USG210, USG310, USG1100, U
Same weakness CWE-287 – Improper Authentication
View allSame technique Authentication Bypass
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External POC / Exploit Code
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