CVEs / CVE-2023-27992
CVE-2023-27992: Zyxel Multiple NAS Devices Command Injection Vulnerability
- Known exploited in the CISA KEV catalog since 23 Jun 2023
- critical 9.8 CVSS 3.1 (from the CNA)
- EPSS 82.2% chance of exploitation in the next 30 days, higher than 99% of CVEs (30 Oct 2026)
- Last changed at its sources
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Summary
Multiple Zyxel network-attached storage (NAS) devices contain a pre-authentication command injection vulnerability that could allow an unauthenticated attacker to execute commands remotely via a crafted HTTP request.
Description
The pre-authentication command injection vulnerability in the Zyxel NAS326 firmware versions prior to V5.21(AAZF.14)C0, NAS540 firmware versions prior to V5.21(AATB.11)C0, and NAS542 firmware versions prior to V5.21(ABAG.11)C0 could allow an unauthenticated attacker to execute some operating system (OS) commands remotely by sending a crafted HTTP request.
Affected and fixed versions
| Product | Affected | Fixed in |
|---|---|---|
| Zyxel NAS326 firmware | < V5.21(AAZF.14)C0 | — |
| Zyxel NAS540 firmware | < V5.21(AATB.11)C0 | — |
| Zyxel NAS542 firmware | < V5.21(ABAG.11)C0 | — |
Exploitation
| In CISA KEV since | 23 Jun 2023 |
|---|---|
| Due date for US federal agencies | 14 Jul 2023 |
| Used in ransomware campaigns | Unknown |
| Required action | Apply updates per vendor instructions. |
Severity
| CVSS 3.1 | 9.8 criticalCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:HScored by the CNA ([email protected]) |
|---|---|
| Weakness | CWE-78 |
References
- CVE-2023-27992 on NVD
- CVE-2023-27992 in the CISA KEV catalog
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-pre-authentication-command-injection-vulnerability-in-nas-products (cited by CISA)
- https://www.zyxel.com/global/en/support/security-advisories/zyxel-security-advisory-for-pre-authentication-command-injection-vulnerability-in-nas-products Patch, Vendor Advisory
- https://www.cisa.gov/known-exploited-vulnerabilities-catalog?field_cve=CVE-2023-27992 US Government Resource
Sources
Exploitation status from the CISA Known Exploited Vulnerabilities catalog. EPSS scores from FIRST. Descriptions, severity and references from the National Vulnerability Database. Open-source package versions from OSV (CC-BY 4.0). Text is shown as each source states it; Stackurity does not edit it. Check the vendor's advisory before acting.
This product uses data from the NVD API but is not endorsed or certified by the NVD.