CVE-2021-4029: zyxel armor z1 (nbg6816) firmware OS Command Injection
CVSS: 8.8v3.1HighModified
Published 22-02-2022Last modified 03-08-2024
Vulnerability summary
CVE-2021-4029 is a high (CVSS 8.8) OS Command Injection vulnerability in zyxel armor z1 (nbg6816) firmware. EPSS estimates a 0.75% chance of exploitation in the next 30 days, higher than 54% of scored vulnerabilities.
CVSS score
8.8/10
010
High · v3.1 (CVE.org)EPSS score
0.75%
0%100%
Low · 0.00 pp in 30 daysKEVNot listedIn no KEV catalog
RansomwareNone recordedNo known use recorded
Public exploits0No public exploits recorded
Timeline
- 22-02-2022PublishedVulnerability first disclosed.
- 03-08-2024Last modifiedVulnerability information updated.
Description
A command injection vulnerability in the CGI program of the Zyxel ARMOR Z1/Z2 firmware could allow an attacker to execute arbitrary OS commands via a LAN interface.
CVSS metrics
3 scores · 2 sources · 2 versionsHigh 8.8Preferred score · CVE.org (CNA)
CVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HSourcesAll 2 agree
- NVDNIST8.8HighCVSS:3.1/AV:A/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
High 8.3Preferred score · NVD (NIST)
AV:A/AC:L/Au:N/C:C/I:C/A:CSourcesSingle source
EPSS trend
Probability
0.75%
Chance of exploitation in the next 30 days
Percentile
54%
Versus all other CVEs
30-day change
0.00 pp
From 0.75% on 20-09-2026
20-09-202620-10-2026
EPSS score0.75%
Known exploited
Compare KEV catalogsNot in any of the 3 tracked catalogs.
Public exploits
0 foundNo public exploits indexed.
Weaknesses
CWE · root causeAffected systems
Zyxel4 products
- armor z1 (nbg6816) firmware1.00(AAWB.10)C0
- armor z2 (nbg6817) firmware1.00(ABCS.10)C0
- nbg6816_firmware1.00\(aawb.10\)c0
- nbg6817_firmware< 1.00\(abcs.11\)c0
1 vendor · 4 products
References
1 links- www.zyxel.com/support/forgery-vulnerabilities-of-select-Armor-home-routers.shtmlX Refsource CONFIRMVendor Advisory