Exploited
critical
10
CWE
77 78
Advisory Published
Updated

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

First published: Wed Mar 04 2020(Updated: )

Multiple ZyXEL network-attached storage (NAS) devices running firmware version 5.21 contain a pre-authentication command injection vulnerability, which may allow a remote, unauthenticated attacker to execute arbitrary code on a vulnerable device. ZyXEL NAS devices achieve authentication by using the weblogin.cgi CGI executable. This program fails to properly sanitize the username parameter that is passed to it. If the username parameter contains certain characters, it can allow command injection with the privileges of the web server that runs on the ZyXEL device. Although the web server does not run as the root user, ZyXEL devices include a setuid utility that can be leveraged to run any command with root privileges. As such, it should be assumed that exploitation of this vulnerability can lead to remote code execution with root privileges. By sending a specially-crafted HTTP POST or GET request to a vulnerable ZyXEL device, a remote, unauthenticated attacker may be able to execute arbitrary code on the device. This may happen by directly connecting to a device if it is directly exposed to an attacker. However, there are ways to trigger such crafted requests even if an attacker does not have direct connectivity to a vulnerable devices. For example, simply visiting a website can result in the compromise of any ZyXEL device that is reachable from the client system. Affected products include: NAS326 before firmware V5.21(AAZF.7)C0 NAS520 before firmware V5.21(AASZ.3)C0 NAS540 before firmware V5.21(AATB.4)C0 NAS542 before firmware V5.21(ABAG.4)C0 ZyXEL has made firmware updates available for NAS326, NAS520, NAS540, and NAS542 devices. Affected models that are end-of-support: NSA210, NSA220, NSA220+, NSA221, NSA310, NSA310S, NSA320, NSA320S, NSA325 and NSA325v2

Credit: cret@cert.org cret@cert.org

Affected SoftwareAffected VersionHow to fix
Zyxel Multiple Network-Attached Storage (NAS) Devices
Zyxel NAS326<5.21\(aazf.7\)c0
Zyxel NAS326
Zyxel NAS520 Firmware<5.21\(aasz.3\)c0
Zyxel NAS520 Firmware
Zyxel NAS540 Firmware<5.21\(aatb.4\)c0
Zyxel NAS540 Firmware
Zyxel NAS542 Firmware<5.21\(abag.4\)c0
Zyxel NAS542 firmware
Zyxel ZyWall ATP100 Firmware>=4.35<4.35\(abps.3\)c0
Zyxel ATP100 Firmware
Zyxel ATP200 firmware>=4.35<4.35\(abfw.3\)c0
Zyxel Zywall ATP200
Zyxel ATP500 Firmware>=4.35<4.35\(abfu.3\)c0
Zyxel ATP500 Firmware
Zyxel Zywall ATP800 Firmware>=4.35<4.35\(abiq.3\)c0
Zyxel ATP series firmware
Zyxel USG20W-VPN Firmware>=4.35<4.35\(abaq.3\)c0
Zyxel USG20W-VPN Firmware
Zyxel USG 20W-VPN Firmware>=4.35<4.35\(abar.3\)c0
Zyxel USG20W-VPN Firmware
Zyxel USG 40 firmware>=4.35<4.35\(aala.3\)c0
Zyxel USG 40
Zyxel USG 40w firmware>=4.35<4.35\(aalb.3\)c0
Zyxel USG 40w firmware
Zyxel USG 60W firmware>=4.35<4.35\(aaky.3\)c0
Zyxel USG 60
Zyxel USG 60W firmware>=4.35<4.35\(aakz.3\)c0
Zyxel USG 60W firmware
Zyxel USG 110 Firmware>=4.35<4.35\(aaph.3\)c0
Zyxel USG 110
Zyxel USG firmware>=4.35<4.35\(aapi.3\)c0
Zyxel USG210 Firmware
Zyxel USG 310 firmware>=4.35<4.35\(aapj.3\)c0
Zyxel USG 310
Zyxel USG 1100 firmware>=4.35<4.35\(aapk.3\)c0
Zyxel USG1100 firmware
Zyxel USG1900 Firmware>=4.35<4.35\(aapl.3\)c0
Zyxel USG1900 Firmware
Zyxel USG2200-VPN Firmware>=4.35<4.35\(abae.3\)c0
Zyxel USG2200-VPN
Zyxel Zywall VPN 50 Firmware>=4.35<4.35\(abhl.3\)c0
Zyxel VPN50 Firmware
Zyxel VPN100>=4.35<4.35\(abfv.3\)c0
Zyxel Zywall VPN100
Zyxel Zywall VPN 300 Firmware>=4.35<4.35\(abfc.3\)c0
Zyxel Zywall VPN300
Zyxel VPN1000 Firmware>=4.35<4.35\(abip.3\)c0
Zyxel VPN1000 Firmware
Zyxel Zywall 110>=4.35<4.35\(aaaa.3\)c0
Zyxel Zywall 110
Zyxel Zywall 310 Firmware>=4.35<4.35\(aaab.3\)c0
Zyxel Zywall 310 Firmware
Zyxel Zywall 1100 Firmware>=4.35<4.35\(aaac.3\)c0
Zyxel Zywall 1100 Firmware
All of
Zyxel NAS326<5.21\(aazf.7\)c0
Zyxel NAS326
All of
Zyxel NAS520 Firmware<5.21\(aasz.3\)c0
Zyxel NAS520 Firmware
All of
Zyxel NAS540 Firmware<5.21\(aatb.4\)c0
Zyxel NAS540 Firmware
All of
Zyxel NAS542 Firmware<5.21\(abag.4\)c0
Zyxel NAS542 firmware
All of
Zyxel ZyWall ATP100 Firmware>=4.35<4.35\(abps.3\)c0
Zyxel ATP100 Firmware
All of
Zyxel ATP200 firmware>=4.35<4.35\(abfw.3\)c0
Zyxel Zywall ATP200
All of
Zyxel ATP500 Firmware>=4.35<4.35\(abfu.3\)c0
Zyxel ATP500 Firmware
All of
Zyxel Zywall ATP800 Firmware>=4.35<4.35\(abiq.3\)c0
Zyxel ATP series firmware
All of
Zyxel USG20W-VPN Firmware>=4.35<4.35\(abaq.3\)c0
Zyxel USG20W-VPN Firmware
All of
Zyxel USG 20W-VPN Firmware>=4.35<4.35\(abar.3\)c0
Zyxel USG20W-VPN Firmware
All of
Zyxel USG 40 firmware>=4.35<4.35\(aala.3\)c0
Zyxel USG 40
All of
Zyxel USG 40w firmware>=4.35<4.35\(aalb.3\)c0
Zyxel USG 40w firmware
All of
Zyxel USG 60W firmware>=4.35<4.35\(aaky.3\)c0
Zyxel USG 60
All of
Zyxel USG 60W firmware>=4.35<4.35\(aakz.3\)c0
Zyxel USG 60W firmware
All of
Zyxel USG 110 Firmware>=4.35<4.35\(aaph.3\)c0
Zyxel USG 110
All of
Zyxel USG firmware>=4.35<4.35\(aapi.3\)c0
Zyxel USG210 Firmware
All of
Zyxel USG 310 firmware>=4.35<4.35\(aapj.3\)c0
Zyxel USG 310
All of
Zyxel USG 1100 firmware>=4.35<4.35\(aapk.3\)c0
Zyxel USG1100 firmware
All of
Zyxel USG1900 Firmware>=4.35<4.35\(aapl.3\)c0
Zyxel USG1900 Firmware
All of
Zyxel USG2200-VPN Firmware>=4.35<4.35\(abae.3\)c0
Zyxel USG2200-VPN
All of
Zyxel Zywall VPN 50 Firmware>=4.35<4.35\(abhl.3\)c0
Zyxel VPN50 Firmware
All of
Zyxel VPN100>=4.35<4.35\(abfv.3\)c0
Zyxel Zywall VPN100
All of
Zyxel Zywall VPN 300 Firmware>=4.35<4.35\(abfc.3\)c0
Zyxel Zywall VPN300
All of
Zyxel VPN1000 Firmware>=4.35<4.35\(abip.3\)c0
Zyxel VPN1000 Firmware
All of
Zyxel Zywall 110>=4.35<4.35\(aaaa.3\)c0
Zyxel Zywall 110
All of
Zyxel Zywall 310 Firmware>=4.35<4.35\(aaab.3\)c0
Zyxel Zywall 310 Firmware
All of
Zyxel Zywall 1100 Firmware>=4.35<4.35\(aaac.3\)c0
Zyxel Zywall 1100 Firmware

Remedy

ZyXEL has made firmware updates available for NAS326, NAS520, NAS540, NAS542, ATP100, ATP200, ATP500, ATP800, USG20-VPN, USG20W-VPN, USG40, USG40W, USG60, USG60W, USG110, USG210, USG310, USG1100, USG1900, USG2200, VPN50, VPN100, VPN300, VPN1000, ZyWALL110, ZyWALL310, and ZyWALL1100 devices.

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