CVE-2021-35029

Home/CVE/An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versio

CVE

An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versio

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.

CRITICAL · CVSS 9.8 EPSS 0.00196

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CVSS base score ≥ 7.0

Sigma rules0 YARA rules0

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Weakness Classification

CWE-287Improper Authentication

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Affected Products & Versions

zyxel usg1900 firmware>= 4.35 and <= 4.64
zyxel usg1100 firmware>= 4.35 and <= 4.64
zyxel usg310 firmware>= 4.35 and <= 4.64
zyxel usg210 firmware>= 4.35 and <= 4.64
zyxel usg110 firmware>= 4.35 and <= 4.64
zyxel usg40 firmware>= 4.35 and <= 4.64
zyxel usg40w firmware>= 4.35 and <= 4.64
zyxel usg60 firmware>= 4.35 and <= 4.64
Show all 37 affected productszyxel usg60w firmware>= 4.35 and <= 4.64
zyxel usg300 firmware>= 4.35 and <= 4.64
zyxel usg1000 firmware>= 4.35 and <= 4.64
zyxel usg2000 firmware>= 4.35 and <= 4.64
zyxel usg20 firmware>= 4.35 and <= 4.64
zyxel usg20w firmware>= 4.35 and <= 4.64
zyxel usg50 firmware>= 4.35 and <= 4.64
zyxel usg100 firmware>= 4.35 and <= 4.64
zyxel usg200 firmware>= 4.35 and <= 4.64
zyxel usg flex 100 firmware>= 4.35 and <= 5.01
zyxel usg flex 200 firmware>= 4.35 and <= 5.01
zyxel usg flex 500 firmware>= 4.35 and <= 5.01
zyxel usg flex 100w firmware>= 4.35 and <= 5.01
zyxel usg flex 700 firmware>= 4.35 and <= 5.01
zyxel zywall atp100 firmware>= 4.35 and <= 5.01
zyxel zywall atp100w firmware>= 4.35 and <= 5.01
zyxel zywall atp200 firmware>= 4.35 and <= 5.01
zyxel zywall atp500 firmware>= 4.35 and <= 5.01
zyxel zywall atp700 firmware>= 4.35 and <= 5.01
zyxel zywall atp800 firmware>= 4.35 and <= 5.01
zyxel zywall vpn50 firmware>= 4.35 and <= 5.01
zyxel zywall vpn100 firmware>= 4.35 and <= 5.01
zyxel zywall vpn300 firmware>= 4.35 and <= 5.01
zyxel usg20-vpn firmware>= 4.35 and <= 5.01
zyxel usg20w-vpn firmware>= 4.35 and <= 5.01
zyxel usg2200-vpn firmware>= 4.35 and <= 5.01
zyxel zywall 110 firmware>= 4.35 and <= 5.01
zyxel zywall 310 firmware>= 4.35 and <= 5.01
zyxel zywall 1100 firmware>= 4.35 and <= 5.01

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Scoring & Timeline

9.8

CRITICAL · CVSS v3.1 · security@zyxel.com.tw

View on NVD

Attack Vector

Network Adjacent Local Physical

Attack Complexity

Low High

Privileges Required

None Low High

User Interaction

None Required

Scope

Unchanged Changed

Confidentiality

None Low High

Integrity

None Low High

Availability

None Low High

Published to NVD02 Jul 2021 · 11:15 AM

CVSS VectorCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H

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References & Sources

Source URLs (vendor pages, mailing lists, write-ups). Exploit/PoC links are in their own section above to avoid duplication.

https://www.zyxel.com/support/Zyxel_security_advisory_for_attacks_against_security_appliances.shtmlVendor Advisory

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