CVE-2023-33010: Zyxel Multiple Firewalls Buffer Overflow Vulnerability
Actively exploited. At least one CVE in this advisory is listed in the CISA Known Exploited Vulnerabilities catalog — exploitation has been observed in the wild. Treat remediation 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 ID processing 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 that could allow remote code execution and denial-of-service conditions.
- Who is affected
- Deployments of Zyxel ATP, USG FLEX, and other specified firewalls are affected.
- Urgency
- Remediation is critical due to active exploitation and the severity of the vulnerability.
- Action
- Apply the latest firmware updates to affected Zyxel firewalls.
AI-assisted analysis generated from the source advisory — verify against the original.
Details
Original advisory: https://nvd.nist.gov/vuln/detail/CVE-2023-33010
Exploitation outlook
EPSS (FIRST.org) estimates each CVE’s probability of exploitation in the next 30 days — here is the CSIRTS.com read on those numbers.
- Exploitation confirmedCVE-2023-33010Already exploited in the wild (CISA KEV) — the prediction phase is over. Patch now. Riskier than 98% of all scored CVEs.
Referenced CVEs
| CVE | CSIRTS overview | External |
|---|---|---|
| CVE-2023-33010 | coverage & exploitation status | NVD · CVE.org |
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