Shortcut: If you have been warned specifically about the IPMI vulnerability (watch out for the tag: 750x7ipmi in the subject),

• your machine(s) has been found by a hacker using metasploit;
• we found his scan results on a hacked machine that we have analysed;
• you can jump directly to  specific notes regarding IPMI.

Bitcoin Mining Hack "750x7" - Technical Details for Detection & Recovery

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• Dell iDRAC: Best Practices for Security for iDRAC, IPMI, SNMP
• Dell iDRAC: Vulnerability Note VU#843044 (Dec. 2014)
• Cisco: IPMI Security Vulnerabilities
• Dan Farmer about IPMI security: http://fish2.com/ipmi/
• Metasploit: A Penetration Tester's Guide to IPMI and BMCs
• Article about ipmi vulnerabilities: Many servers expose insecure out-of-band management interfaces to the Internet

Others

• rkhunter (Rootkit detection tool): http://rkhunter.sourceforge.net

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