From a VHDX File to a Remcos RAT, (Tue, Jun 16th)

2026-06-16T13:23:45Z320441a60cb4155a019ab9b278ae494bbb7f5e82d628eaef3f12c4a5975bee05
RATRemcosVHDXWindows automatic mountZIP archivearchive evasionmalicious JavaScriptmalware deliverythreat intel

What happened

Report of a malicious ZIP (SHA256: a0104921a2d37ab87482ac9a9f5c3713479c118846c3e999178e75b81620c094) that contains a VHDX. When mounted (automatic on modern Windows), the VHDX exposes a malicious JavaScript which was used to deliver/execute the Remcos remote access trojan (RAT). Attackers are using VHDX inside archives to bypass simple archive/file inspection and leverage automatic mounting behavior on Windows to trigger payloads without explicit user actions.

Why it matters

A reviewed impact interpretation has not been published for this record.

Evidence and limitations

Source ID
sans_isc_diary
Record identifier
320441a60cb4155a019ab9b278ae494bbb7f5e82d628eaef3f12c4a5975bee05
Enrichment time
2026-06-16T13:23:45Z
AI-assisted enrichment
Yes

This record may overlap with other records. Its enrichment can be incomplete or wrong, and machine assistance was used. Validate consequential decisions against the linked source and your own environment.