CVE-2021-35029
No exploitation reported by the sources we read.
- Published2021-07-02
- WeaknessCWE-287
Am I affected?
Debian, Ubuntu or Red Hat sometimes backport a fix without changing the upstream version number: such a version reads « to verify », never « affected ».With a domain, we read the version its public headers and pages expose. A distribution build can carry the fix under an older number.
Description
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.
Timeline
dates in UTC- 2021-07-0211:15CVE publishedNVD
Observed activity
isMalicious corpus · updated 2026-10-23 18:48 UTCBlock these indicators
- Firewall list (EDL, text): https://api.ismalicious.com/edl/cve/CVE-2021-35029?format=txt
- CSV export: https://api.ismalicious.com/edl/cve/CVE-2021-35029?format=csv
- TAXII collection of exploited CVEs
- The EDL and CSV take an API key on the Pro plan.
Versions per branch
NVD| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 5.1 | ≥ 4.35, ≤ 5.01 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 5.1 | ≥ 4.35, ≤ 5.01 | no fix published | NVD |
| Branch | Affected | Fixed in | Source |
|---|---|---|---|
| 5.1 | ≥ 4.35, ≤ 5.01 | no fix published | NVD |
34 more products in the sources.
as publishedRanges as NVD and OSV publish them; a distribution’s build can be fixed under an older number.
Fix
Advisories and patches
- www.zyxel.comVendor Advisory
Detection
- Nuclei template
- none so far ProjectDiscovery
- Exploit-DB
- no entry Exploit-DB
- Proof-of-concept repositories
- none listed PoC-in-GitHub
Sources
Technical details
- CVSS v3 Vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- Published
- 2021-07-02
- Last Modified
- 2026-06-17
- NVD status
- Modified
Frequently asked questions
What is CVE-2021-35029?
Is CVE-2021-35029 actively exploited?
What is the CVSS score for CVE-2021-35029?
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