Known exploited vulnerability
CVE-2023-33009
The short answer
CVE-2023-33009 affects Zyxel ATP series firmware and is rated critical (CVSS 9.8). CISA added it to the Known Exploited Vulnerabilities catalog on 2023-06-05: attackers are using it, so patch it first.
What it is
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.
Weakness: CWE-120.
Severity
9.8 critical
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Exploited (CISA KEV)
Yes, since Jun 5, 2023
Federal due date Jun 26, 2023
EPSS, next 30 days
28%
Higher than 98% of scored CVEs
How it can be exploited
- Attack vector
- Network
- Attack complexity
- Low
- Privileges required
- None
- User interaction
- None
- Scope
- Unchanged
- Confidentiality impact
- High
- Integrity impact
- High
- Availability impact
- High
What CISA says to do
Apply updates per vendor instructions.
Affected products
ATP series firmware, USG FLEX series firmware, USG FLEX 50(W) firmware, USG20(W)-VPN firmware, VPN series firmware, ZyWALL/USG series firmware. NVD's record lists the exact affected versions.
References
- www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls Vendor Advisory
- www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-multiple-buffer-overflow-vulnerabilities-of-firewalls Vendor Advisory
- www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-33009 US Government Resource
Questions
Is CVE-2023-33009 being exploited?
Yes. CISA added CVE-2023-33009 to its Known Exploited Vulnerabilities catalog on 2023-06-05, with a federal remediation due date of 2023-06-26.
How do I fix CVE-2023-33009?
CISA's required action: Apply updates per vendor instructions.
From NVD, CISA KEV, FIRST EPSS and OSV.dev, checked . Status on NVD: Analyzed. The description is NVD's text, quoted as published.
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