Rewterz Threat Update – Russian Threat Actors Breached Ukrainian Telecom Operator and Wiped Thousands of Systems

Severity

High

Analysis Summary

Russian-linked threat actors who breached Kyivstar, Ukraine’s largest telecommunications service provider, have wiped thousands of systems on the main network of the telecom operator. The incident left about 25 million of the company’s mobile and home internet subscribers without an internet connection.

The attackers breached Kyivstar’s network back in May 2023 as discovered by Ukrainian cybersecurity researchers. They launched the attack months after the initial breach and wiped all of the virtual servers and computers, destroying the core of the telecoms operator. The Ukrainian security company was able to prevent multiple attempts to cause more damage to the operator. Researchers are investigating individual samples of the malware that was used by the adversary and it is clear that the attack was planned carefully for many months in advance.

The cyberattack has a significant impact on the country’s civilians but it didn’t disrupt any notable military communications. This could be because of the Ukrainian Defense Forces utilizing different algorithms and communication protocols. After the breach occurred, the CEO of Kyivstar and the cybersecurity company suggested that threat actors from Russia may have been behind the operation especially due to the conflict between Russia and Ukraine.

Soon, the attack was claimed by Russian attackers from the Solntsepek group which is believed to be linked to the Russian military APT group named Sandworm. They stated to have wiped 10,000 computers and over four thousand servers on Kyivstar’s network. Their aim was to disrupt communications because the company provides its services to the Armed Forces of Ukraine, law enforcement agencies, and government agencies.

Researchers have confirmed that Sandworm was behind the December breach in Kyivstar, stating that the Russian military intelligence carried out several other cyberattacks that targeted Ukrainian organizations, especially ISPs and telecom operators. It is revealed that Sandworm has breached the networks of 11 Ukrainian telecom providers since May 2023, resulting in service interruptions after the attackers deployed scripts during the final stages of the attacks to wipe Mikrotik backups and equipment to make recovery a challenging task.

Impact

• Operational Disruption
• Data Loss

Remediation

• Implement multi-factor authentication (MFA) on all accounts to add an extra layer of security to login processes.
• Consider the use of phishing-resistant authenticators to further enhance security. These types of authenticators are designed to resist phishing attempts and provide additional protection against social engineering attacks.
• Regularly monitor network activity for any unusual behavior, as this may indicate that a cyberattack is underway.
• Organizations need to stay vigilant and follow best practices for cybersecurity to protect their systems and data from potential threats. This includes regularly updating software and implementing strong access controls and monitoring tools.
• Develop a comprehensive incident response plan to respond effectively in case of a security breach or data leakage.
• Maintain regular backups of critical data and systems to ensure data recovery in case of a security incident.
• Adhere to security best practices, including the principle of least privilege, and ensure that users and applications have only the necessary permissions.
• Establish a robust patch management process to ensure that security patches are evaluated, tested, and applied promptly.
• Conduct security audits and assessments to evaluate the overall security posture of your systems and networks.
• Implement network segmentation to contain and isolate potential threats to limit their impact on critical systems.
• Never trust or open links and attachments received from unknown sources/senders.