CVE-2023-34139
CVE-2023-34139 is a high-severity vulnerability in Zyxel Usg 2200-vpn Firmware with a CVSS 3.x base score of 8.8. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-78.
Key facts
- Severity: High (CVSS 3.x base score 8.8)
- EPSS exploit prediction: 1% (54th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-78
- Affected product: Zyxel Usg 2200-vpn Firmware
- Published:
- Last modified:
Description
A command injection vulnerability in the Free Time WiFi hotspot feature of the Zyxel USG FLEX series firmware versions 4.50 through 5.36 Patch 2 and VPN series firmware versions 4.20 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands on an affected device.
Frequently asked questions
- What is CVE-2023-34139?
- A command injection vulnerability in the Free Time WiFi hotspot feature of the Zyxel USG FLEX series firmware versions 4.50 through 5.36 Patch 2 and VPN series firmware versions 4.20 through 5.36 Patch 2, could allow an unauthenticated, LAN-based attacker to execute some OS commands on an affected device.
- How severe is CVE-2023-34139?
- CVE-2023-34139 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-2023-34139 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 1% (54th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2023-34139?
- CVE-2023-34139 primarily affects Zyxel Usg 2200-vpn Firmware. In total, 15 product configurations (CPEs) are listed as vulnerable; see the affected-products list for the exact versions.
- How do I fix CVE-2023-34139?
- 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-2023-34139 published?
- CVE-2023-34139 was published on 2023-07-17 and last updated on 2026-06-17.
References
Affected products (15)
- 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_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 2200-vpn Firmware
- CVE-2023-33012 — High (CVSS 8.8): A command injection vulnerability in the configuration parser of the Zyxel ATP series firmware versions 5.10 through…
- 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-2023-34141 — High (CVSS 8.0): A command injection vulnerability in the access point (AP) management feature of the Zyxel ATP series firmware versions…
- CVE-2023-34138 — High (CVSS 8.0): A command injection vulnerability in the hotspot management feature of the Zyxel ATP series firmware versions 4.60…
- CVE-2022-30526 — High (CVSS 7.8): A privilege escalation vulnerability was identified in the CLI command of Zyxel USG FLEX 100(W) firmware versions 4.50…
All CVEs affecting Zyxel Usg 2200-vpn Firmware →
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