CVE-2023-33012
CVE-2023-33012 is a high-severity vulnerability in Zyxel Usg 20w-vpn Firmware with a CVSS 3.x base score of 8.8. Its EPSS exploit-prediction score of 10% places it in the 95th percentile, indicating an elevated likelihood of exploitation. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 10% (95th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Zyxel Usg 20w-vpn Firmware
- Published:
- Last modified:
Description
A command injection vulnerability in the configuration parser of the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series firmware versions 5.00 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 5.10 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 5.10 through 5.36 Patch 2, and VPN series firmware versions 5.00 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands by using a crafted GRE configuration when the cloud management mode is enabled.
Frequently asked questions
- What is CVE-2023-33012?
- A command injection vulnerability in the configuration parser of the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series firmware versions 5.00 through 5.36 Patch 2, USG FLEX 50(W) series firmware versions 5.10 through 5.36 Patch 2, USG20(W)-VPN series firmware versions 5.10 through 5.36 Patch 2, and VPN series firmware versions 5.00 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands by using a crafted GRE configuration when the cloud management mode is enabled.
- How severe is CVE-2023-33012?
- CVE-2023-33012 has a CVSS 3.x base score of 8.8, rated high severity. It is exploitable over an adjacent network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is high, integrity high, and availability high.
- Is CVE-2023-33012 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 10% (95th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-33012?
- CVE-2023-33012 primarily affects Zyxel Usg 20w-vpn Firmware. In total, 22 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-33012?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2023-33012 published?
- CVE-2023-33012 was published on 2023-07-17 and last updated on 2026-06-17.
References
Affected products (22)
- cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_2200-vpn_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp100_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp100w_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp200_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp500_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp700_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_atp800_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn100_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn2s_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn300_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn50_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn_100_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn_300_firmware:*:*:*:*:*:*:*:*
- cpe:2.3:o:zyxel:zywall_vpn_50_firmware:*:*:*:*:*:*:*:*
More vulnerabilities in Zyxel Usg 20w-vpn Firmware
- CVE-2023-33010 — Critical (CVSS 9.8): A buffer overflow vulnerability in the ID processing function in Zyxel ATP series firmware versions 4.32 through 5.36…
- CVE-2023-33009 — Critical (CVSS 9.8): A buffer overflow vulnerability in the notification function in Zyxel ATP series firmware versions 4.60 through 5.36…
- CVE-2023-33011 — High (CVSS 8.8): A format string vulnerability in the Zyxel ATP series firmware versions 5.10 through 5.36 Patch 2, USG FLEX series…
- CVE-2023-28767 — High (CVSS 8.8): The configuration parser fails to sanitize user-controlled input in the Zyxel ATP series firmware versions 5.10 through…
- CVE-2023-27991 — High (CVSS 8.8): The post-authentication command injection vulnerability in the CLI command of Zyxel ATP series firmware versions 4.32…
- CVE-2023-22916 — High (CVSS 8.1): The configuration parser of Zyxel ATP series firmware versions 5.10 through 5.35, USG FLEX series firmware versions…
All CVEs affecting Zyxel Usg 20w-vpn Firmware →
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