CVE-2020-9054
Zyxel Multiple NAS Devices OS Command Injection Vulnerability
Severity Score
Exploit Likelihood
Affected Versions
Public Exploits
2Exploited in Wild
YesDecision
Descriptions
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
Múltiples dispositivos network-attached storage (NAS) de ZyXEL cuando ejecutan la versión de firmware 5.21 contienen una vulnerabilidad de inyección de comando previa a la autenticación, que puede permitir a un atacante remoto no autenticado ejecutar código arbitrario sobre un dispositivo vulnerable. Los dispositivos NAS de ZyXEL alcanzan la autenticación utilizando el archivo ejecutable CGI weblogin.cgi. Este programa no puede sanear apropiadamente el parámetro username que se le pasó. Si el parámetro de username contiene determinados caracteres, puede permitir una inyección de comandos con los privilegios del servidor web que se ejecuta en el dispositivo ZyXEL. Aunque el servidor web no es ejecutado como el usuario root, los dispositivos ZyXEL incluyen una utilidad setuid que puede ser aprovechada para ejecutar cualquier comando con privilegios root. Como tal, se debe suponer que la explotación de esta vulnerabilidad puede conducir a la ejecución remota de código con privilegios root. Mediante el envío de una petición HTTP POST o GET especialmente diseñada hacia un dispositivo ZyXEL vulnerable, un atacante remoto no autenticado puede ejecutar código arbitrario en el dispositivo. Esto puede presentarse al conectar directamente a un dispositivo si es expuesto directamente a un atacante. Sin embargo, existen maneras de activar tales peticiones diseñadas inclusive si un atacante no posee conectividad directa con dispositivos vulnerables. Por ejemplo, simplemente visitando un sitio web puede comprometer cualquier dispositivo ZyXEL al que se pueda acceder desde el sistema cliente. Los productos afectados incluyen: NAS326 antes de la versión de firmware V5.21(AAZF.7)C0, NAS520 antes de la versión de firmware V5.21(AASZ.3)C0, NAS540 antes de la versión de firmware V5.21(AATB.4)C0 NAS542 antes de la versión de firmware V5.21(ABAG.4)C0. ZyXEL ha puesto a disposición actualizaciones de firmware para dispositivos NAS326, NAS520, NAS540 y NAS542. Modelos afectados que se encuentran en el final del soporte: NSA210, NSA220, NSA220+, NSA221, NSA310, NSA310S, NSA320, NSA320S, NSA325 y NSA325v2.
Multiple Zyxel network-attached storage (NAS) devices contain a pre-authentication command injection vulnerability, which may allow a remote, unauthenticated attacker to execute arbitrary code.
CVSS Scores
SSVC
- Decision:-
Timeline
- 2020-02-18 CVE Reserved
- 2020-03-04 CVE Published
- 2021-09-09 First Exploit
- 2022-03-25 Exploited in Wild
- 2022-04-15 KEV Due Date
- 2024-09-16 CVE Updated
- 2024-09-28 EPSS Updated
CWE
- CWE-78: Improper Neutralization of Special Elements used in an OS Command ('OS Command Injection')
CAPEC
References (6)
| URL | Tag | Source |
|---|---|---|
| https://cwe.mitre.org/data/definitions/78.html | Third Party Advisory | |
| https://kb.cert.org/artifacts/cve-2020-9054.html | Third Party Advisory |
|
| https://kb.cert.org/vuls/id/498544 | Third Party Advisory |
|
| URL | Date | SRC |
|---|---|---|
| https://github.com/darrenmartyn/CVE-2020-9054 | 2021-09-09 | |
| https://krebsonsecurity.com/2020/02/zyxel-fixes-0day-in-network-storage-devices | 2024-09-16 |
| URL | Date | SRC |
|---|
| URL | Date | SRC |
|---|---|---|
| https://www.zyxel.com/support/remote-code-execution-vulnerability-of-NAS-products.shtml | 2020-03-06 |
Affected Vendors, Products, and Versions
| Vendor | Product | Version | Other | Status | ||||||
|---|---|---|---|---|---|---|---|---|---|---|
| Vendor | Product | Version | Other | Status | <-- --> | Vendor | Product | Version | Other | Status |
| Zyxel Search vendor "Zyxel" | Nas326 Firmware Search vendor "Zyxel" for product "Nas326 Firmware" | < 5.21\(aazf.7\)c0 Search vendor "Zyxel" for product "Nas326 Firmware" and version " < 5.21\(aazf.7\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Nas326 Search vendor "Zyxel" for product "Nas326" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Nas520 Firmware Search vendor "Zyxel" for product "Nas520 Firmware" | < 5.21\(aasz.3\)c0 Search vendor "Zyxel" for product "Nas520 Firmware" and version " < 5.21\(aasz.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Nas520 Search vendor "Zyxel" for product "Nas520" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Nas540 Firmware Search vendor "Zyxel" for product "Nas540 Firmware" | < 5.21\(aatb.4\)c0 Search vendor "Zyxel" for product "Nas540 Firmware" and version " < 5.21\(aatb.4\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Nas540 Search vendor "Zyxel" for product "Nas540" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Nas542 Firmware Search vendor "Zyxel" for product "Nas542 Firmware" | < 5.21\(abag.4\)c0 Search vendor "Zyxel" for product "Nas542 Firmware" and version " < 5.21\(abag.4\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Nas542 Search vendor "Zyxel" for product "Nas542" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Atp100 Firmware Search vendor "Zyxel" for product "Atp100 Firmware" | >= 4.35 < 4.35\(abps.3\)c0 Search vendor "Zyxel" for product "Atp100 Firmware" and version " >= 4.35 < 4.35\(abps.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Atp100 Search vendor "Zyxel" for product "Atp100" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Atp200 Firmware Search vendor "Zyxel" for product "Atp200 Firmware" | >= 4.35 < 4.35\(abfw.3\)c0 Search vendor "Zyxel" for product "Atp200 Firmware" and version " >= 4.35 < 4.35\(abfw.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Atp200 Search vendor "Zyxel" for product "Atp200" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Atp500 Firmware Search vendor "Zyxel" for product "Atp500 Firmware" | >= 4.35 < 4.35\(abfu.3\)c0 Search vendor "Zyxel" for product "Atp500 Firmware" and version " >= 4.35 < 4.35\(abfu.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Atp500 Search vendor "Zyxel" for product "Atp500" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Atp800 Firmware Search vendor "Zyxel" for product "Atp800 Firmware" | >= 4.35 < 4.35\(abiq.3\)c0 Search vendor "Zyxel" for product "Atp800 Firmware" and version " >= 4.35 < 4.35\(abiq.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Atp800 Search vendor "Zyxel" for product "Atp800" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg20-vpn Firmware Search vendor "Zyxel" for product "Usg20-vpn Firmware" | >= 4.35 < 4.35\(abaq.3\)c0 Search vendor "Zyxel" for product "Usg20-vpn Firmware" and version " >= 4.35 < 4.35\(abaq.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg20-vpn Search vendor "Zyxel" for product "Usg20-vpn" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg20w-vpn Firmware Search vendor "Zyxel" for product "Usg20w-vpn Firmware" | >= 4.35 < 4.35\(abar.3\)c0 Search vendor "Zyxel" for product "Usg20w-vpn Firmware" and version " >= 4.35 < 4.35\(abar.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg20w-vpn Search vendor "Zyxel" for product "Usg20w-vpn" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg40 Firmware Search vendor "Zyxel" for product "Usg40 Firmware" | >= 4.35 < 4.35\(aala.3\)c0 Search vendor "Zyxel" for product "Usg40 Firmware" and version " >= 4.35 < 4.35\(aala.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg40 Search vendor "Zyxel" for product "Usg40" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg40w Firmware Search vendor "Zyxel" for product "Usg40w Firmware" | >= 4.35 < 4.35\(aalb.3\)c0 Search vendor "Zyxel" for product "Usg40w Firmware" and version " >= 4.35 < 4.35\(aalb.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg40w Search vendor "Zyxel" for product "Usg40w" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg60 Firmware Search vendor "Zyxel" for product "Usg60 Firmware" | >= 4.35 < 4.35\(aaky.3\)c0 Search vendor "Zyxel" for product "Usg60 Firmware" and version " >= 4.35 < 4.35\(aaky.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg60 Search vendor "Zyxel" for product "Usg60" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg60w Firmware Search vendor "Zyxel" for product "Usg60w Firmware" | >= 4.35 < 4.35\(aakz.3\)c0 Search vendor "Zyxel" for product "Usg60w Firmware" and version " >= 4.35 < 4.35\(aakz.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg60w Search vendor "Zyxel" for product "Usg60w" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg110 Firmware Search vendor "Zyxel" for product "Usg110 Firmware" | >= 4.35 < 4.35\(aaph.3\)c0 Search vendor "Zyxel" for product "Usg110 Firmware" and version " >= 4.35 < 4.35\(aaph.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg110 Search vendor "Zyxel" for product "Usg110" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg210 Firmware Search vendor "Zyxel" for product "Usg210 Firmware" | >= 4.35 < 4.35\(aapi.3\)c0 Search vendor "Zyxel" for product "Usg210 Firmware" and version " >= 4.35 < 4.35\(aapi.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg210 Search vendor "Zyxel" for product "Usg210" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg310 Firmware Search vendor "Zyxel" for product "Usg310 Firmware" | >= 4.35 < 4.35\(aapj.3\)c0 Search vendor "Zyxel" for product "Usg310 Firmware" and version " >= 4.35 < 4.35\(aapj.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg310 Search vendor "Zyxel" for product "Usg310" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg1100 Firmware Search vendor "Zyxel" for product "Usg1100 Firmware" | >= 4.35 < 4.35\(aapk.3\)c0 Search vendor "Zyxel" for product "Usg1100 Firmware" and version " >= 4.35 < 4.35\(aapk.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg1100 Search vendor "Zyxel" for product "Usg1100" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg1900 Firmware Search vendor "Zyxel" for product "Usg1900 Firmware" | >= 4.35 < 4.35\(aapl.3\)c0 Search vendor "Zyxel" for product "Usg1900 Firmware" and version " >= 4.35 < 4.35\(aapl.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg1900 Search vendor "Zyxel" for product "Usg1900" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Usg2200 Firmware Search vendor "Zyxel" for product "Usg2200 Firmware" | >= 4.35 < 4.35\(abae.3\)c0 Search vendor "Zyxel" for product "Usg2200 Firmware" and version " >= 4.35 < 4.35\(abae.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Usg2200 Search vendor "Zyxel" for product "Usg2200" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Vpn50 Firmware Search vendor "Zyxel" for product "Vpn50 Firmware" | >= 4.35 < 4.35\(abhl.3\)c0 Search vendor "Zyxel" for product "Vpn50 Firmware" and version " >= 4.35 < 4.35\(abhl.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Vpn50 Search vendor "Zyxel" for product "Vpn50" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Vpn100 Firmware Search vendor "Zyxel" for product "Vpn100 Firmware" | >= 4.35 < 4.35\(abfv.3\)c0 Search vendor "Zyxel" for product "Vpn100 Firmware" and version " >= 4.35 < 4.35\(abfv.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Vpn100 Search vendor "Zyxel" for product "Vpn100" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Vpn300 Firmware Search vendor "Zyxel" for product "Vpn300 Firmware" | >= 4.35 < 4.35\(abfc.3\)c0 Search vendor "Zyxel" for product "Vpn300 Firmware" and version " >= 4.35 < 4.35\(abfc.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Vpn300 Search vendor "Zyxel" for product "Vpn300" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Vpn1000 Firmware Search vendor "Zyxel" for product "Vpn1000 Firmware" | >= 4.35 < 4.35\(abip.3\)c0 Search vendor "Zyxel" for product "Vpn1000 Firmware" and version " >= 4.35 < 4.35\(abip.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Vpn1000 Search vendor "Zyxel" for product "Vpn1000" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Zywall110 Firmware Search vendor "Zyxel" for product "Zywall110 Firmware" | >= 4.35 < 4.35\(aaaa.3\)c0 Search vendor "Zyxel" for product "Zywall110 Firmware" and version " >= 4.35 < 4.35\(aaaa.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Zywall110 Search vendor "Zyxel" for product "Zywall110" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Zywall310 Firmware Search vendor "Zyxel" for product "Zywall310 Firmware" | >= 4.35 < 4.35\(aaab.3\)c0 Search vendor "Zyxel" for product "Zywall310 Firmware" and version " >= 4.35 < 4.35\(aaab.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Zywall310 Search vendor "Zyxel" for product "Zywall310" | - | - |
Safe
|
| Zyxel Search vendor "Zyxel" | Zywall1100 Firmware Search vendor "Zyxel" for product "Zywall1100 Firmware" | >= 4.35 < 4.35\(aaac.3\)c0 Search vendor "Zyxel" for product "Zywall1100 Firmware" and version " >= 4.35 < 4.35\(aaac.3\)c0" | - |
Affected
| in | Zyxel Search vendor "Zyxel" | Zywall1100 Search vendor "Zyxel" for product "Zywall1100" | - | - |
Safe
|