Summary:
On June 20th, one of Indonesia’s temporary National Data Centers suffered from a cyberattack that led to the encryption of the government’s servers and disruption of immigration services, passport control, issuing of event permits, and other online services. The Indonesian government has attributed this attack to a new ransomware operation, dubbed Brain Cipher, which has allegedly demanded a $8 million ransom be paid in the form of Monero cryptocurrency in exchange for a decryptor key and for data allegedly stolen from the attack to not be leaked to the public. As of writing, it’s unclear how the actors got initial access or exactly what type of data was allegedly stolen. The Indonesian government is currently carrying out an investigation and is making efforts to restore various public services affected by the cyberattack.

Security Officer Comments:
Based on samples of Brain Cipher ransomware uploaded online, researchers have concluded that Brain Cipher’s encryptor was created using LockBit’s version 3.0 builder that was leaked by a disgruntled developer back in 2022. Taking a closer examination, minor changes have been made to Brain Cipher’s encryptor, where the ransomware will not only append an extension to the encrypted file but also encrypt the file name as well, making it difficult for victims to recover important documents and files. Upon successful encryption, Brain Cipher will leave behind a ransom note ([extension].README.txt) on the victim’s system, which contains a link to a Tor negotiation site used for ransom payments. In this case, each victim is provided a unique encryption ID that they can use to access the site and communicate with the ransomware gang. Like any other ransomware operation, Brain Cipher has a data leak site where it will threaten to post victims’ data if a ransom is not paid. As of writing, the group’s data leak site does not have any listings, indicating that negotiations are still ongoing with the Indonesian government.

Suggested Corrections:
Backup your data, system images, and configurations, regularly test them, and keep the backups offline: Ensure that backups are regularly tested and that they are not connected to the business network, as many ransomware variants try to find and encrypt or delete accessible backups. Maintaining current backups offline is critical because if your network data is encrypted with ransomware, your organization can restore systems.

Update and patch systems promptly: This includes maintaining the security of operating systems, applications, and firmware in a timely manner. Consider using a centralized patch management system; use a risk-based assessment strategy to drive your patch management program.

Test your incident response plan: There's nothing that shows the gaps in plans more than testing them. Run through some core questions and use those to build an incident response plan: Are you able to sustain business operations without access to certain systems? For how long? Would you turn off your manufacturing operations if business systems such as billing were offline?

Check Your Security Team's Work: Use a 3rd party pen tester to test the security of your systems and your ability to defend against a sophisticated attack. Many ransomware criminals are aggressive and sophisticated and will find the equivalent of unlocked doors.

Segment your networks: There's been a recent shift in ransomware attacks – from stealing data to disrupting operations. It's critically important that your corporate business functions and manufacturing/production operations are separated and that you carefully filter and limit internet access to operational networks, identify links between these networks and develop workarounds or manual controls to ensure ICS networks can be isolated and continue operating if your corporate network is compromised. Regularly test contingency plans such as manual controls so that safety critical functions can be maintained during a cyber incident.

Train employees: Email remains the most vulnerable attack vector for organizations. Users should be trained how to avoid and spot phishing emails. Multi Factor authentication can help prevent malicious access to sensitive services.

Link(s):
https://www.bleepingcomputer.com/ne...nsomware-behind-indonesia-data-center-attack/