RondoDox Unveiled: Breaking Down a New Botnet Threat
Summary:
FortiGuard Labs has identified a sharp increase in exploitation attempts tied to the RondoDox botnet, which targets critical vulnerabilities in TBK DVR devices and Four-Faith routers, enabling remote attackers to execute arbitrary commands and fully compromise systems. Originally observed using ELF binaries on ARM and MIPS, RondoDox has expanded its targeting to a broad range of Linux architectures, including x86-64 and AArch64, allowing it to impact a wide variety of DVRs, routers, and IoT devices across different environments.
RondoDox uses XOR obfuscation to hide its configuration data, employs custom-built libraries, and implements layered persistence methods by modifying system startup files, creating symbolic links, and adding entries to crontabs to ensure it remains operational even if defenders remove one persistence vector. It actively terminates security analysis and system monitoring tools to evade detection and deletes execution histories to limit forensic visibility. The botnet is capable of launching DDoS attacks using HTTP, UDP, and TCP protocols, disguising its malicious traffic to mimic legitimate traffic from gaming, VPN, and communication platforms, making detection and blocking challenging. Additionally, RondoDox scans system directories for key system binaries related to firewall management and system shutdown processes, renaming them to random strings to disrupt system stability and complicate recovery efforts.
Security Officer Comments:
RondoDox’s infection process includes checking for writable and executable directories to ensure successful payload deployment while suppressing system signals to resist termination attempts. Its use of multi-layered persistence, evasion tactics, and traffic mimicry demonstrates its advanced capabilities, enabling it to maintain long-term access on compromised devices while facilitating impactful DDoS campaigns.
Suggested Corrections:
https://www.fortinet.com/blog/threat-research/rondobox-unveiled-breaking-down-a-botnet-threat
FortiGuard Labs has identified a sharp increase in exploitation attempts tied to the RondoDox botnet, which targets critical vulnerabilities in TBK DVR devices and Four-Faith routers, enabling remote attackers to execute arbitrary commands and fully compromise systems. Originally observed using ELF binaries on ARM and MIPS, RondoDox has expanded its targeting to a broad range of Linux architectures, including x86-64 and AArch64, allowing it to impact a wide variety of DVRs, routers, and IoT devices across different environments.
RondoDox uses XOR obfuscation to hide its configuration data, employs custom-built libraries, and implements layered persistence methods by modifying system startup files, creating symbolic links, and adding entries to crontabs to ensure it remains operational even if defenders remove one persistence vector. It actively terminates security analysis and system monitoring tools to evade detection and deletes execution histories to limit forensic visibility. The botnet is capable of launching DDoS attacks using HTTP, UDP, and TCP protocols, disguising its malicious traffic to mimic legitimate traffic from gaming, VPN, and communication platforms, making detection and blocking challenging. Additionally, RondoDox scans system directories for key system binaries related to firewall management and system shutdown processes, renaming them to random strings to disrupt system stability and complicate recovery efforts.
Security Officer Comments:
RondoDox’s infection process includes checking for writable and executable directories to ensure successful payload deployment while suppressing system signals to resist termination attempts. Its use of multi-layered persistence, evasion tactics, and traffic mimicry demonstrates its advanced capabilities, enabling it to maintain long-term access on compromised devices while facilitating impactful DDoS campaigns.
Suggested Corrections:
- Patch affected devices: Apply security updates for TBK DVRs and Four-Faith routers immediately to address the exploited vulnerabilities.
- Limit internet exposure: Remove direct internet access to device admin interfaces; if needed, use VPNs and IP allowlisting for remote management.
- Harden configurations: Change default passwords, disable unused services, and segment DVRs and IoT devices onto separate VLANs to reduce exposure.
- Monitor for anomalies: Enable logging and monitor for unusual outbound traffic, failed login attempts, and signs of persistence or DDoS activity.
- Prepare incident response: Establish procedures to isolate, clean, and restore compromised devices while verifying system file integrity.
https://www.fortinet.com/blog/threat-research/rondobox-unveiled-breaking-down-a-botnet-threat