TI-2023-04129 Aliases CVE-2023-4473 GHSA-2h5j-5qmh-v4qh

OS command injection in Zyxel NAS326 firmware

HIGH 82CWE-78Published 2023-11-30 · Updated 2025-12-16

Key facts

Attack vector: 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 web server of the Zyxel NAS326 firmware version V5.21(AAZF.14)C0 and NAS542 firmware version V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands by sending a crafted URL to a vulnerable device.

Why it matters now

Exploitation Proof of concept CISA SSVC · not in CISA KEV

EPSS 0.41348 98th percentileScored 2026-11-07

Fix No fix listed No fixed version in the sources yet

SSVC decision points

CISA ADP · SSVC 2.0.3

Exploitation: Poc
Automatable: Yes
Technical impact: Total

The decision (Track, Attend, Act) also depends on your mission and well-being impact; see CISA's SSVC guide.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
Zyxel	NAS326 firmware	V5.21(AAZF.14)C0	—	No fix listed	CNA
Zyxel	NAS542 firmware	V5.21(ABAG.11)C0	—	No fix listed	CNA

NAS326 firmware VendorZyxel Affected V5.21(AAZF.14)C0 Fixed in — No fix listed CNA
NAS542 firmware VendorZyxel Affected V5.21(ABAG.11)C0 Fixed in — No fix listed CNA

CPE configurations NVD · 4

CPE	Versions	Role	Vendor
cpe:2.3:o:zyxel:nas326_firmware::::::::	up to 5.21\(aazf.14\)c0	Vulnerable	Zyxel
cpe:2.3:h:zyxel:nas326:-:::::::*	not specified by NVD	Running on	Zyxel
cpe:2.3:o:zyxel:nas542_firmware::::::::	up to 5.21\(abag.11\)c0	Vulnerable	Zyxel
cpe:2.3:h:zyxel:nas542:-:::::::*	not specified by NVD	Running on	Zyxel

cpe:2.3:o:zyxel:nas326_firmware:*:*:*:*:*:*:*:* Versions up to 5.21\(aazf.14\)c0 Vulnerable ·Zyxel
cpe:2.3:h:zyxel:nas326:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel
cpe:2.3:o:zyxel:nas542_firmware:*:*:*:*:*:*:*:* Versions up to 5.21\(abag.11\)c0 Vulnerable ·Zyxel
cpe:2.3:h:zyxel:nas542:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel

Remediation

No fixed version listed by the sources yet.

Fixed in the same release

Records fixed by the same vendor advisory or release, as the CNA lists them.

Advisory · 2023-11-30
Zyxel NAS326 firmware, NAS542 firmware — zyxel.com/global/en/support/security-advisories/zyxel-secur…
6 records Highest priority Priority HIGH 4 HIGH, 1 MEDIUM, 1 LOW
Other records, highest priority first
- TI-2023-04130 OS command injection in Zyxel NAS326 firmwarePriority HIGH 82
- TI-2023-19361 OS command injection in Zyxel NAS326 firmwarePriority HIGH 72
- TI-2023-17584 OS command injection in Zyxel NAS326 firmwarePriority HIGH 70
Show all 6 records → Advisory →

Timeline

2026-10-02 Threatist record created from CVE-2023-4473
2026-10-03 Alias added: GHSA-2h5j-5qmh-v4qh

References

Patch 1

https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-authentication-bypass-and-command-injection-vulnerabilities-in-nas-products

Other 1

https://bugprove.com/knowledge-hub/cve-2023-4473-and-cve-2023-4474-authentication-bypass-and-multiple-blind-os-command-injection-vulnerabilities-in-zyxel-s-nas-326-devices/

TI-2023-12582 OS command injection in Zyxel NAS326 firmware KEVCVSS 3.1CRITICAL 9.8
TI-2020-07267 OS command injection in Zyxel NAS326 KEVCVSS 3.1CRITICAL 9.8
TI-2024-19735 OS command injection in Zyxel NAS326 firmware CVSS 3.1CRITICAL 9.8
TI-2024-19736 OS command injection in Zyxel NAS326 firmware CVSS 3.1CRITICAL 9.8
TI-2023-04130 OS command injection in Zyxel NAS326 firmware CVSS 3.1CRITICAL 9.8
TI-2023-19361 OS command injection in Zyxel NAS326 firmware CVSS 3.1HIGH 8.8

See all 23 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences