CRITICALCVSS v3.1 9.8Actively exploited · CISA KEV since 2023-06-05Vulnerability
CVE-2023-33009
Zyxel ATP, USG FLEX, USG FLEX 50(W), USG20(W)-VPN, VPN, and ZyWALL/USG firewalls contain a buffer overflow vulnerability in the notification function that could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and remote code execution on an affected device.
Properties
- Euvd product
- ATP series firmware, USG FLEX series firmware, USG FLEX 50(W) firmware, ZyWALL/USG series firmware, VPN series Firmware, USG20(W)-VPN firmware
- Vulnerability name
- Zyxel Multiple Firewalls Buffer Overflow Vulnerability
- First seen
- 2025-10-21T23:05:47+00:00
- Cvss score
- 9.8
- Epss score
- 0.28144
- Last seen
- 2026-10-19T12:00:27+00:00
- Due date
- 2023-06-26
- Euvd assigner
- Zyxel
- Retrieved at
- 2026-10-21T01:24:47+00:00
- Exploited euvd since
- 2023-06-05T00:00:00+00:00
- Src batch id
- epss_history-20261020T103617Z-728ddd
- Source url
- https://epss.empiricalsecurity.com/epss_scores-2026-10-19.csv.gz
- Date added
- 2023-06-05
- Score
- 9.8
- Euvd base score version
- 3.1
- Fetched at
- 2026-10-20T10:36:20+00:00
- Euvd vendor
- Zyxel
- Cvss vector
- CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
- In Signal since
- initial import (Sep 2026)
- Euvd base score
- 9.8
Related Entities (95 · showing 23)
AFFECTS_PRODUCT (92 · showing 20)
DESCRIBES (1)
HAS_WEAKNESS (1)
INVOLVES (1)
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