Attackers actively targeting vulnerable Dasan GPON home routers

November 19, 2020

SonicWall Capture Labs threat research team observed attacks exploiting old vulnerabilities in Dasan GPON home routers. DASAN Zhone Solutions is a provider of  network access solutions for service provider and enterprise networks. The company provides a wide array of reliable, cost-effective networking technologies—including broadband access, Ethernet switching, Passive Optical LAN and software-defined networks.
Attackers are targeting following two vulnerabilities in GPON home routers:

Authentication Bypass Vulnerability
It is possible to bypass authentication simply by appending "?images" to any URL of the device that requires authentication. For example by the /menu.html?images/ or /GponForm/diag_FORM?images/ URI. Attacker can then manage the device.(CVE-2018-10561)

Command Injection Vulnerability
Command Injection vulnerability exists in Dasan GPON home routers via the dest_host parameter in a diag_action=ping request to a GponForm/diag_Form URI.The router saves ping results in tmp directory and displays them when user visits diag.html. This can be used to inject and execute commands.(CVE-2018-10562)

Following exploit is spotted in the wild

The attacker takes advantage of the above vulnerabilities to bypass authetication by appending "?images" to the POST request. Then the attacker downloads a malicious executable by injecting "wget"  command. This is saved in the tmp directory and is executed when a user visits diag.html page.

SonicWall Capture Labs provides protection against this threat via following signatures:

    • IPS 13340:Dasan GPON Routers Command Injection
    • GAV:Mirai.H

Threat Graph


A quick look at Shodan reveals thousands of vulnerable devices