SilverFox has expanded its malware toolkit by targeting a Japanese industrial manufacturer through an email campaign disguised as a fake invoice This article explores silverfox expanded malware. . The attackers lured recipients into downloading a ZIP archive from legitimate-looking services, then used trusted software to load a malicious component without altering the signed application.
The malware also tries to minimize detection by restoring a clean in-memory copy of a core Windows library, which may remove some user-level security hooks but does not completely eliminate protection from kernel logging, network monitoring, or behavior-based detection. Notable signs include suspicious DLL loading from temporary folders, service creation with vulnerable drivers, suspended processes followed by memory modifications, unusual Registry writes, and repeated watchdog activity.
**RC4 Key:** - Hardcoded key used to decrypt embedded resources - Prefix: `01ccc662c4b5d6ff79ede2e5d` - Sample hash reported in source: `0a0353fddca1ba1432b35411a PDFCORE8.dll sample hash prefix reported in the source` - Prefix: `0ef3119504f8aa3a534bfdbe2 Downloader sample hash prefix reported in the source` - Sample hashes reported in source: `1355d2d73a1f21b4fa4e1b974`, `31a276aae8a45873beecf4137`, `36eb85e475954e2815c40e0c1`, `5e9c2eb32e1c5e0e9f69c8eda` **Batch Watchdog Script:** - Hash prefix reported in source: `c0ec1488902568be9a4960c67 BootRepair.sys hash prefix reported in the source` - Sample hashes reported in source: `1f0f08699f74eb2fb690edd06 EnPortv.sys hash prefix reported in the source`, `381dbc9012d02b3a42916813b wsftprm.sys hash prefix reported in the source` **Note:** - IP addresses and domains are intentionally defanged to prevent accidental resolution or hyperlinking.
