CVE-2023-33009
Zyxel Multiple Firewalls Buffer Overflow Vulnerability
This vulnerability is in the CISA Known Exploited Vulnerabilities catalog: attackers are using it. If you run Multiple Firewalls, fix it now.
CISA required action: Apply updates per vendor instructions.
US federal civilian agencies must remediate by Jun 26, 2023.
Patch status
No official fix confirmed yet
Until a fix ships, follow the vendor's mitigations and CISA's required action, limit exposure of affected systems, and watch this record for a patch.
Description
A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36 Patch 1, USG FLEX series firmware versions 4.60 through 5.36 Patch 1, USG FLEX 50(W) firmware versions 4.60 through 5.36 Patch 1, USG20(W)-VPN firmware versions 4.60 through 5.36 Patch 1, VPN series firmware versions 4.60 through 5.36 Patch 1, ZyWALL/USG series firmware versions 4.60 through 4.73 Patch 1, could allow an unauthenticated attacker to cause denial-of-service (DoS) conditions and even a remote code execution on an affected device.
Source: NIST National Vulnerability Database. Official vulnerability data, reproduced as published.
Affected products
| Product | Vendor | Source |
|---|---|---|
| Multiple Firewalls | Zyxel | KEV |
Sources: KEV = CISA Known Exploited Vulnerabilities catalog. Version details have not been published yet.
Intelligence timeline
Developments from the last 30 days, newest first.
- CVSS scoredUpdateKEV
CVE-2023-33009 scored CVSS 9.8: Zyxel Multiple Firewalls, Zyxel Multiple Firewalls Buffer Overflow Vulnerability
CISA lists this as exploited in the wild. Unpatched Multiple Firewalls systems are exposed to active attacks now.
Basis: NIST National Vulnerability Database
1 earlier event is available with a subscription. See plans.
Coverage
We have not published a story about this vulnerability yet.