CVE-2021-35029 json
An authentication bypasss vulnerability in the web-based management interface of Zyxel USG/Zywall series firmware versions 4.35 through 4.6…
published 2021-07-02 5 y ago modified 2026-06-17 4 mo ago also EUVD-2021-21676
- cvss
- 9.8
- version 3.1, CNA
- cisa kev
- Not listed
- not in CISA's catalog
- epss
- 2.3%
- EPSS 2.3% chance of exploitation in 30 days, percentile 83%
- public exploits
- 0
- none known
Summary
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.
Exploit prediction
2.25% chance of exploitation in the next 30 days, higher than 83% of all scored CVEs (FIRST EPSS, 2026-11-08).
CVSS scores
| assigned by | version | score | vector |
|---|---|---|---|
| CNA | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 3.1 | 9.8 | CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H |
| NVD | 2.0 | 7.5 | AV:N/AC:L/Au:N/C:P/I:P/A:P |
Affected products
- Zyxel USG/Zywall series Firmware
- Zyxel USG FLEX series Firmware
- Zyxel ATP series Firmware
- Zyxel VPN series Firmware
Classification
- Weakness
-
- CWE-287 Improper Authentication
References
Sources
- CVE List CVE-2021-35029
- NVD CVE-2021-35029
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