Threat actors are increasingly using blockchain to hide and distribute malicious data and C2 instructions. Nozomi Networks researchers track Glupteba activity on the Bitcoin blockchain, showing how OP_RETURN data, XOR encryption, and Tor-based C2 are used, with guidance on how defenders can hunt for these artifacts.
Keypoints
- Glupteba is a backdoor trojan delivered via Pay-Per-Install networks and infected installers or cracks.
- The malware can deploy additional modules from a credential stealer to exploit IoT devices from vendors like MikroTik and Netgear.
- Glupteba uses the Bitcoin blockchain (OP_RETURN) to store and distribute C2 domains, making takedowns difficult.
- Early variants used AES-GCM for payload protection; newer variants use XOR encryption with a fixed key (e.g., “cheesesauce”).
- TOR hidden services began being used as C2 servers in 2021, increasing resilience and anonymity.
- Researchers identify four Glupteba campaigns (2019–2022) spanning multiple wallets and addresses, and they map associated domains and TLS/certificate activity.
- Defenders are advised to block blockchain-related domains and monitor DNS logs, TLS cert activity, and keep antivirus updated.
MITRE Techniques
- [T1105] Ingress Tool Transfer – The operators can deploy additional modules from the credential stealer to exploit kits on infected systems. ‘the botnet operators can deploy additional modules from the credential stealer to exploit kits’
- [T1090] Proxy – Tor – Glupteba started using TOR hidden services as C2 servers, enhancing anonymity. ‘TOR hidden services were used as a command-and-control server by Glupteba’
- [T1027] Obfuscated/Compressed Data – The payload is protected by an XOR encryption scheme in newer variants. ‘a XOR encryption scheme to protect the data’
- [T1583] Acquire Infrastructure – The operation relies on infrastructure such as blockchain-based domains and TLS/certificate activities; certificate registrations are noted. ‘Let’s encrypt certificate registration’ and various domain registrations are described
Indicators of Compromise
- [Domain] C2 domains – cdneurops[.]pics, mastiakele[.]icu, mastiakele[.]xyz, cdneurops[.]buzz, cdneurops[.]shop
- [Domain] Associated domains – limeprime[.]org, greenphoenix[.]xyz, revouninstaller[.]homes, getyourgift[.]life
- [Wallet Address] Wallet addresses – 12EfzLra6LttQ8RWvBTDzJUjYE6eRxx4TY, 14XZhcCJDguZuZF4p13tfLXJ6puudY7gqs, 15nWGFaodg3efVKATgsaaSPU2TxSbiMHcP, 19RzEN3pqHvgRHGMjjtYCqjVTXt8bnHkK3, 1KfLXEveeDEi58wvuBBxuywUA1V66F5QXK
- [Wallet Address] Additional addresses – 1CUhaTe3AiP9Tdr4B6wedoe9vNsymLiD97, 1CzetoTU29WbhNy1UozrQpxuFuCVxffbTd, 1HjoomvzjtvZdbznoEijTNAkMjmsFba9fY
Read more: https://www.nozominetworks.com/blog/tracking-malicious-glupteba-activity-through-the-blockchain/