# CVE-2022-34747

## Summary

- **CVE ID:** CVE-2022-34747
- **Severity:** CRITICAL
- **CVSS Score:** 9.8 (CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H)
- **CWE:** CWE-134
- **Published:** Sep 6, 2022
- **Last Modified:** Mar 13, 2026

## Description

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.

## Affected Products

- Zyxel — Zyxel NAS326 firmware (< V5.21(AAZF.12)C0)

## References

- [CNA](https://www.zyxel.com/support/Zyxel-security-advisory-for-format-string-vulnerability-in-NAS.shtml)

## Exploitation Prediction (EPSS)

- **EPSS Score:** 1.73%
- **EPSS Percentile:** 76.5

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_Exported from OnDuty AI Vulnerability Intelligence on 2026-09-18._