CVE-2023-33009
Zyxel Multiple Firewalls Buffer Overflow Vulnerability
IN CISA KEV
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.
- Vendor
- Zyxel
- Product
- Multiple Firewalls
- CVSS
- No score recorded (no NVD record loaded for this entry)
- CWE
- CWE-120
- Published
- Not recorded
- NVD modified
- Not recorded
CISA KEV
- Date added
- 2023-06-05
- Due date
- 2023-06-26
- Ransomware use
- Unknown
- Required action
- Apply updates per vendor instructions.
EPSS
28.1% chance of exploitation in the next 30 days (percentile 98th)
FIRST EPSS, updated 17 Oct 2026. About EPSS
CVSS is severity, EPSS is likelihood, KEV means already exploited. EPSS is a statistical probability, not a certainty: a low score does not make a bug safe, and a high one does not prove it is being exploited.
Data last updated 18 Oct 2026. Sources: NVD API 2.0, CISA KEV catalog, FIRST EPSS. Links: NVD, CISA KEV. Metadata only. ThreatWire does not host exploit code.