Rewterz Threat Alert – Hive Ransomware – Active IOCs

Severity

High

Analysis Summary

Hive is one of the quickest evolving ransomware families which was first observed in June 2021 and likely operates as an affiliate-based ransomware, employs a wide variety of tactics, techniques, and procedures (TTPs), creating significant challenges for defense and mitigation. Hive ransomware uses multiple mechanisms to compromise business networks, including phishing emails with malicious attachments to gain access and Remote Desktop Protocol (RDP) to move laterally once on the network. After compromising a victim network, Hive ransomware actors exfiltrate data and encrypt files on the network. The actors leave a ransom note in each affected directory within a victim’s system, which provides instructions on how to purchase the decryption software. The ransom note also threatens to leak exfiltrated victim data on the Tor site, “HiveLeaks.”

The latest variant introduced by this ransomware is written in Rust languaguage as opposed to the previous variants, which were written in GoLang or Go. 
According to researchers:

The new variation employs a unique collection of algorithms, including Elliptic Curve Diffie-Hellmann (ECDH) with Curve25519 and XChaCha20-Poly1305″ (authenticated encryption with ChaCha20 symmetric cipher)

The latest Hive version approaches file encryption in a distinctive manner. It produces two sets of keys in memory, uses them to encrypt files, and then encrypts and writes the sets to the root of the drive it encrypts, with a .key extension. 

Impact

• Unauthorized Access
• Data Exfiltration
• File Encryption

Indicators of Compromise

MD5

• be5c5a4b6ed6953857c3cf4fd24503c0

SHA-256

• 8a461e66ae8a53ffe98d1e2e1dc52d015c11d67bd9ed09eb4be2124efd73ccd5

SHA-1

• f58feb3cf1611346078353382082dc1c8cbac60f

Remediation

• Search for IOCs in your environment.
• Block all threat indicators at your respective controls.
• Maintain cyber hygiene by updating your anti-virus software and implement patch management lifecycle.
• Maintain Offline Backups – In a ransomware attack, the adversary will often delete or encrypt backups if they have access to them. That’s why it’s important to keep offline (preferably off-site), encrypted backups of data and test them regularly.
• Emails from unknown senders should always be treated with caution.
• Never trust or open ” links and attachments received from unknown sources/senders.