A new botnet named Goldoon has been identified by cybersecurity researchers as targeting old vulnerabilities in D-Link routers, specifically exploiting a critical security flaw from nearly a decade ago, CVE-2015-2051. This vulnerability allows remote attackers to execute arbitrary commands on D-Link DIR-645 routers through specially crafted HTTP requests. Once a device is compromised, attackers can gain complete control over the router, enabling them to extract system information, establish communication with a command-and-control (C2) server, and use the device to launch additional attacks, such as distributed denial-of-service (DDoS).
The Goldoon botnet begins its infection process by exploiting CVE-2015-2051 to retrieve a dropper script from a remote server. This script is responsible for downloading a next-stage payload compatible with various Linux system architectures. Once executed, the payload acts as a downloader for the Goldoon malware from another remote endpoint, after which the dropper erases the executed files and deletes itself to cover its tracks and evade detection.
Apart from establishing persistence on the host using multiple autorun methods, Goldoon communicates with a C2 server to receive further malicious instructions. It boasts a sophisticated capability to perform DDoS attacks using 27 different methods across various protocols including DNS, HTTP, ICMP, TCP, and UDP. The exploitation of the CVE-2015-2051 vulnerability, despite being an old and well-documented flaw, underscores a persistent challenge in cybersecurity: many devices remain unpatched and vulnerable to known exploits, providing fertile ground for botnet operations.
This development highlights the ongoing trend of botnets evolving to exploit as many devices as possible, serving not only as platforms for launching attacks but also as means for anonymization and proxying malicious activities. Cybersecurity firms note that compromised routers are often rented out to other criminals or used by nation-state actors to obscure their operations, integrating these devices into extensive networks that are hard to trace and dismantle. This utilization of compromised routers underlines the importance of maintaining security hygiene, such as regular updates and strong password policies, to protect against such threats.
