OS command injection in Zyxel ARMOR Z2 firmware
Priority LOW 39CWE-78Published · Updated
Key facts
- Attack vector
- Adjacent network
- Privileges required
- None
- User interaction
- None
- Attack complexity
- Low
- Impact type
- Code execution
- Confidentiality · integrity · availability
- High · High · High
- Fix status
- No fix listed
Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-78.
Summary
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.
Why it matters now
EPSS 0.00748 55th percentileScored 2026-11-08
Fix No fix listed No fixed version in the sources yet
SSVC decision points
Not available: CISA has not published SSVC decision points for this record.
Affected products
| Vendor | Product | Affected versions | Fixed in | Status | Source |
|---|---|---|---|---|---|
| Zyxel | ARMOR Z2 (NBG6817) firmware | 1.00(ABCS.10)C0 | — | No fix listed | CNA |
| Zyxel | ARMOR Z1 (NBG6816) firmware | 1.00(AAWB.10)C0 | — | No fix listed | CNA |
- ARMOR Z2 (NBG6817) firmware VendorZyxel Affected 1.00(ABCS.10)C0 Fixed in — No fix listed CNA
- ARMOR Z1 (NBG6816) firmware VendorZyxel Affected 1.00(AAWB.10)C0 Fixed in — No fix listed CNA
CPE configurations NVD · 4
| CPE | Versions | Role | Vendor |
|---|---|---|---|
| cpe:2.3:o:zyxel:nbg6816_firmware:1.00\(aawb.10\)c0:*:*:*:*:*:*:* | 1.00(aawb.10)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:nbg6816:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
| cpe:2.3:o:zyxel:nbg6817_firmware:*:*:*:*:*:*:*:* | before 1.00\(abcs.11\)c0 | Vulnerable | Zyxel |
| cpe:2.3:h:zyxel:nbg6817:-:*:*:*:*:*:*:* | not specified by NVD | Running on | Zyxel |
- cpe:2.3:o:zyxel:nbg6816_firmware:1.00\(aawb.10\)c0:*:*:*:*:*:*:* Versions 1.00(aawb.10)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:nbg6816:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
- cpe:2.3:o:zyxel:nbg6817_firmware:*:*:*:*:*:*:*:* Versions before 1.00\(abcs.11\)c0 Vulnerable ·Zyxel
- cpe:2.3:h:zyxel:nbg6817:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
Remediation
No fixed version listed by the sources yet.
Timeline
- 2026-10-02 Threatist record created from CVE-2021-4029
- 2026-10-03 Alias added: GHSA-47g9-xhm7-62xr
References
More Zyxel Nbg6816 Firmware vulnerabilities
- TI-2021-02919 Cross-site request forgery in Zyxel ARMOR Z2 firmware CVSS 3.1HIGH 8.8
Sources
- CVE-2021-4029 · CVE Program
- CVE-2021-4029 · NVD
- FIRST EPSS
- GHSA-47g9-xhm7-62xr · GitHub Advisory Database · CC BY 4.0
This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences