Severity
High
Analysis Summary
GuLoader is currently being distributed via spam email campaigns with archived attachments that contain the malware. The majority of malware downloaded by GuLoader is commodity malware, with AgentTesla, FormBook, and NanoCore being the most predominant. This downloader typically stores its encrypted payloads on Google Drive. It has also downloaded its payloads from Microsoft OneDrive and also from compromised or attacker-controlled websites. By utilizing legitimate file-sharing websites, GuLoader can evade network-based detection, as these services are not generally filtered or inspected in corporate environments. Usually, the downloaded payloads are encrypted with a hard-coded XOR key embedded in the malware, making it difficult for file-sharing service providers to identify the payload as malicious. This time, GuLoader Shellcode injector is being distributed via a file named “EXTERNAL RFPPAN India Epoxy/PU 2021”. The scope of this campaign so far seems to be global.
Impact
- Malware installation
- Detection evasion
- Information theft
Indicators of Compromise
MD5
- 264a4f1da5163ba11190d5b3cab35418
- 0982098712c5d11babbcde65cb2d463e
- 098d627a93cd7687f54c4bd1c342e00d
SHA-256
- 49d777aff9d282095b6d8e7d26937d579869056e895c23efefbfea2775937f69
- 5f22cc700a2bc2c9e61044ca91e052f7305b46310f1b747c665a22655a64ae70
- 952c1bc7773c529d609f5eac3d5268274cec23eb495ca6ce78a866a73f96aa24
SHA-1
- c6e81fa82210b02cc29ac9905684e043e5db805e
- bb47419b2591e222388a1453533c8ee21e0fe670
- dadf67b338f8223d06312da5d8d4a338dde816f3
Remediation
- Block the threat indicators at their respective controls.
- Do not download files attached in untrusted emails.
- Do not download files from untrusted sources on the internet.
- Search for IOCs in your environment.