The browser blind spot: Why your security tool may not be blocking what you think it is [Guest Diary], (Wed, Jun 17th)
2026-06-17T19:23:46Z•52c2b35e50dab91d7765bd9f99b5a10b8763481824d2639f1baca2d8c2c41a90
base64browser-blind-spotcontent-security-policyframe-ancestorsjavascriptmalicious-zipmsiransomware/ratremcossans-iscsteganographyvhdvhdxweb-securityx-frame-options
What happened
SANS ISC diary entries (mid‑June 2026) covering multiple security topics: a guest diary about a browser "blind spot" where security tools may not block content as expected; a reader report of a malicious ZIP (SHA256 a0104921a2d37ab87482ac9a9f5c3713479c118846c3e999178e75b81620c094) that contains a VHDX which auto‑mounts on modern Windows and exposes a malicious JavaScript leading to a Remcos RAT; analysis of image/MSI steganography ("Evil MSI Background"); and a longitudinal study of framing protection headers (X-Frame-Options and CSP frame-ancestors) across the top 1M domains. Also includes S‑
Why it matters
A reviewed impact interpretation has not been published for this record.
Evidence and limitations
- Source ID
- sans_isc_diary
- Record identifier
- 52c2b35e50dab91d7765bd9f99b5a10b8763481824d2639f1baca2d8c2c41a90
- Enrichment time
- 2026-06-17T19:23:46Z
- AI-assisted enrichment
- Yes
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