DinodasRAT Linux Malware Attack on Linux Servers

DinodasRAT, also known as XDealer, is a sophisticated C++ backdoor targeting multiple operating systems. It is designed to enable attackers to monitor and extract sensitive information from compromised systems covertly.

Notably, a Windows variant of this RAT was employed in attacks against government bodies in Guyana, an operation that was thoroughly analyzed by ESET researchers and named Operation Jacana.

Following ESET’s exposé in early October 2023, a previously unknown Linux variant of DinodasRAT was uncovered.

Indications suggest that this version, labeled V10 by the perpetrators, may have been active since 2022.

However, the first detected Linux variant, V7, dates back to 2021 and has not been publicly detailed. This report delves into the technical aspects of a Linux implant utilized by the attackers.

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Infection and Persistence Mechanisms

The DinodasRAT Linux implant predominantly affects Red Hat-based and Ubuntu distributions. Upon execution, it generates a hidden mutex file to prevent multiple instances from running.

The backdoor achieves persistence through direct execution, SystemV or SystemD startup scripts, and by executing itself with the parent process ID as an argument, complicating detection efforts.

Backdoor main code

Victim Identification and Persistence

The RAT gathers system information and infection timing to create a unique identifier (UID) for the victim’s machine, which does not include user-specific data.

This UID comprises the infection date, an MD5 hash of the system’s hardware report, a random number, and the backdoor version.


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The UID and other relevant details are stored in a hidden file, “/etc/.netc.conf”, which the RAT uses to maintain a profile of the backdoor.

Stealth and Service Manager Utilization

DinodasRAT employs techniques to avoid updating file access times and leverages Systemd and SystemV service managers to ensure its persistence on infected systems.

It determines the Linux distribution type and installs appropriate init scripts to launch the backdoor after network setup.

Command and Control (C2) Communication

The Linux variant communicates with its C2 server using TCP or UDP, with the domain hard-coded into the binary.

The RAT has a variable timed interval for sending information back to the C2, and if the user is root, communication is immediate.

It follows a structured network packet format and recognizes various commands for managing the infected system.

The Linux variant shares encryption methods with its Windows counterpart, using Pidgin’s libqq qq_crypt library functions and the Tiny Encryption Algorithm (TEA) in CBC mode.

It also shares encryption keys with the Windows version for C2 and name encryption.

The infrastructure used by DinodasRAT’s Linux versions was active during the analysis, with one IP address serving both Windows and Linux C2 domains.

The most affected regions include China, Taiwan, Turkey, and Uzbekistan. Kaspersky products detect this Linux variant as HEUR:Backdoor.Linux.Dinodas.a.

The discovery of the Linux variant of DinodasRAT highlights the threat actors’ capability to infiltrate Linux infrastructure. Unlike the Windows-focused Operation Jacana, the Linux variant does not prioritize user information for infection management.

Instead, it relies on hardware-specific data to generate UIDs, emphasizing the goal of maintaining access to Linux servers.

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