CVE-2020-9054: Zyxel Multiple NAS Devices OS Command Injection Vulnerability

CVE-2020-9054 · Severity: critical · CVSS 9.8 · Exploited in the wild · Published 2022-03-25

Multiple Zyxel NAS devices contain a pre-authentication command injection vulnerability in the weblogin.cgi executable due to improper sanitization of the username parameter. A remote, unauthenticated attacker can execute arbitrary code with root privileges by sending specially crafted HTTP requests. This vulnerability has been observed being exploited in the wild.

Vendors: Zyxel.

Quick answers

Is CVE-2020-9054 exploited in the wild?
Yes. CVE-2020-9054 is known to be exploited in the wild, first recorded on 25 March 2022. Treat it as urgent.
How severe is CVE-2020-9054?
Critical severity, with a CVSS score of 9.8, published 25 March 2022.
Which products and versions are affected?
Zyxel NAS326 before V5.21(AAZF.7)C0; Zyxel NAS520 before V5.21(AASZ.3)C0; Zyxel NAS540 before V5.21(AATB.4)C0; Zyxel NAS542 before V5.21(ABAG.4)C0; and 10 more.
Is there a fix for CVE-2020-9054?
No fixed version is recorded yet. Check the vendor's advisory in the references below. If you run it, Junglewise drafts a mitigation that fits your setup and applies it once you approve, with senior security engineers behind it.
How is CVE-2020-9054 attacked?
It is attacked over the network, in a network appliance.
Am I affected by CVE-2020-9054?
Check whether you run Zyxel Multiple Network-Attached Storage (NAS) Devices. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

Affected products

  • Zyxel NAS326 before V5.21(AAZF.7)C0
  • Zyxel NAS520 before V5.21(AASZ.3)C0
  • Zyxel NAS540 before V5.21(AATB.4)C0
  • Zyxel NAS542 before V5.21(ABAG.4)C0
  • Zyxel NSA210 All (End-of-Support)
  • Zyxel NSA220 All (End-of-Support)
  • Zyxel NSA220+ All (End-of-Support)
  • Zyxel NSA221 All (End-of-Support)
  • Zyxel NSA310 All (End-of-Support)
  • Zyxel NSA310S All (End-of-Support)
  • Zyxel NSA320 All (End-of-Support)
  • Zyxel NSA320S All (End-of-Support)
  • Zyxel NSA325 All (End-of-Support)
  • Zyxel NSA325v2 All (End-of-Support)

Timeline

  • 2020-02-24: disclosed: Public disclosure of 0-day vulnerability
  • 2020-03-06: advisory: Initial NVD analysis published
  • 2022-03-25: kev added: Added to CISA Known Exploited Vulnerabilities Catalog

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