CVE-2023-27991
Zyxel · published 2023-04-24
Source record Collected from the National Vulnerability Database (NVD)
Description
Description by Zyxel Corporation via the CVE Program.
The post-authentication command injection vulnerability in the CLI command of Zyxel ATP series firmware versions 4.32 through 5.35, USG FLEX series firmware versions 4.50 through 5.35, USG FLEX 50(W) firmware versions 4.16 through 5.35, USG20(W)-VPN firmware versions 4.16 through 5.35, and VPN series firmware versions 4.30 through 5.35, which could allow an authenticated attacker to execute some OS commands remotely.
Status at the source
- NVD status: Modified
Affected products, as the source lists them
| Vendor | Product | Versions |
|---|---|---|
| Zyxel | ATP series firmware | 4.32 through 5.35: affected |
| Zyxel | USG FLEX series firmware | 4.50 through 5.35: affected |
| Zyxel | USG FLEX 50(W) firmware | 4.16 through 5.35: affected |
| Zyxel | USG20(W)-VPN firmware | 4.16 through 5.35: affected |
| Zyxel | VPN series firmware | 4.30 through 5.35: affected |
Products named in NVD's CPE match criteria (19)
cpe:2.3:o:zyxel:atp200_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:atp100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:atp700_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:atp500_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:atp100w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:atp800_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_50_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_200_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_500_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_700_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_100w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_20w-vpn_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg_flex_50w_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:usg20-vpn_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:vpn100_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:vpn1000_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:vpn300_firmware:*:*:*:*:*:*:*:*cpe:2.3:o:zyxel:vpn50_firmware:*:*:*:*:*:*:*:*
DeSpy has not checked any unit, hardware revision or firmware. A product missing here is not a statement that it is unaffected.
Scores, as their sources published them
- CVSS 3.1: 8.8 HIGH — as published by Zyxel Corporation (Secondary)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - CVSS 3.1: 8.8 HIGH — as published by NIST (Primary)
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H - SSVC — CISA's assessment (SSVC 2.0.3, CISA Coordinator): Exploitation: none · Automatable: no · Technical impact: total
DeSpy does not score records. These are the sources' own values.
Weaknesses
Sources
References the source lists
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-xss-vulnerability-and-post-authentication-command-injection-vulnerability-in-firewalls
Source dates: published 2023-04-24, last changed 2026-06-17. DeSpy's copy of this version is dated 2026-09-28.
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