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CVE-2020-9054 PoC for Zyxel
CVE-2020-9054 An incomplete CVE-2020-9054 PoC I might even finish this sometime, but its been rotting on a hard drive since forever
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 malicious user 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
| Vulnerable Product | Search on Vulmon | Subscribe to Product |
|---|---|---|
zyxel nas326_firmware |
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zyxel nas520_firmware |
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zyxel nas540_firmware |
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zyxel nas542_firmware |
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zyxel atp100_firmware |
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zyxel atp200_firmware |
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zyxel atp500_firmware |
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zyxel atp800_firmware |
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zyxel usg20-vpn_firmware |
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zyxel usg20w-vpn_firmware |
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zyxel usg40_firmware |
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zyxel usg40w_firmware |
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zyxel usg60_firmware |
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zyxel usg60w_firmware |
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zyxel usg110_firmware |
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zyxel usg210_firmware |
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zyxel usg310_firmware |
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zyxel usg1100_firmware |
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zyxel usg1900_firmware |
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zyxel usg2200_firmware |
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zyxel vpn50_firmware |
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zyxel vpn100_firmware |
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zyxel vpn300_firmware |
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zyxel vpn1000_firmware |
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zyxel zywall110_firmware |
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zyxel zywall310_firmware |
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zyxel zywall1100_firmware |
It's 2020 and pre-auth, superuser command injection is still a thing
Zyxel's network storage boxes, business VPN gateways, firewalls, and, er, security scanners can be remotely hijacked by any miscreant, due to a devastating security hole in the firmware. The devices' weblogin.cgi program fails to sanitize user input, allowing anyone who can reach one of these vulnerable machines, over the network or across the internet, can silently inject and execute arbitrary commands as a root superuser with no authentication required. That would be a total compromise. It's a...