CVE-2023-33009
Actively exploited. CVE-2023-33009 is listed in the CISA Known Exploited Vulnerabilities catalog (added 2023-06-05) — exploitation has been observed in the wild, and US federal agencies are required to remediate it under BOD 22-01. Treat patching as urgent.
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.
CSIRTS triage
- What
- Zyxel firewalls contain a buffer overflow vulnerability in the notification function.
- Who is affected
- Deployments of Zyxel ATP, USG FLEX, and other specified firewalls are affected.
- Urgency
- Immediate remediation is necessary due to active exploitation and critical severity.
- Action
- Update the firmware of affected Zyxel firewalls to mitigate the vulnerability.
AI-assisted analysis generated from the source advisory — verify against the original.
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Exploitation outlook
- Exploitation confirmedAlready exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 98% of all EPSS-scored CVEs.
Advisory coverage (1)
- criticalexploitedCVE-2023-33009: Zyxel Multiple Firewalls Buffer Overflow Vulnerabilitycisa-kev · 2023-06-05
External references
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