TI-2022-15557 Aliases CVE-2022-34747 GHSA-p6gf-558m-r8q3

A format string vulnerability in Zyxel NAS326 firmware versions prior to V5.21(AAZF.12)C0…

MEDIUM 46CWE-134Published 2022-09-06 · Updated 2024-08-03

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: Fixed

Attack profile from CVSS 3.1 · CNA. Fix status from CNA. Impact type from CWE-134 and the CVSS impact.

Summary

A format string vulnerability in Zyxel NAS326 firmware versions prior to V5.21(AAZF.12)C0 could allow an attacker to achieve unauthorized remote code execution via a crafted UDP packet.

Why it matters now

EPSS 0.01781 78th percentileScored 2026-11-07

Fix Fixed Zyxel NAS326 firmware (Zyxel): V5.21(AAZF.12)C0

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	Zyxel NAS326 firmware	before V5.21(AAZF.12)C0	V5.21(AAZF.12)C0	Patch available	CNA

Zyxel NAS326 firmware VendorZyxel Affected before V5.21(AAZF.12)C0 Fixed in V5.21(AAZF.12)C0 Patch available CNA

CPE configurations NVD · 2

CPE	Versions	Role	Vendor
cpe:2.3:o:zyxel:nas326_firmware::::::::	before 5.21\(aazf.12\)c0	Vulnerable	Zyxel
cpe:2.3:h:zyxel:nas326:-:::::::*	not specified by NVD	Running on	Zyxel

cpe:2.3:o:zyxel:nas326_firmware:*:*:*:*:*:*:*:* Versions before 5.21\(aazf.12\)c0 Vulnerable ·Zyxel
cpe:2.3:h:zyxel:nas326:-:*:*:*:*:*:*:* Versions not specified by NVD Running on ·Zyxel

Remediation

Fix · CNA Zyxel NAS326 firmware (Zyxel) Fixed in V5.21(AAZF.12)C0

Timeline

2026-10-02 Threatist record created from CVE-2022-34747
2026-10-03 Alias added: GHSA-p6gf-558m-r8q3

References

Patch 1

https://www.zyxel.com/support/Zyxel-security-advisory-for-format-string-vulnerability-in-NAS.shtml

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-2023-04129 OS command injection in Zyxel NAS326 firmware CVSS 3.1CRITICAL 9.8

See all 23 →

Sources

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