From the Field: Role Separation

๐Ÿ”Ž ๐—™๐—ฟ๐—ผ๐—บ ๐˜๐—ต๐—ฒ ๐—™๐—ถ๐—ฒ๐—น๐—ฑ โ€” Real-World Findings from Security Assessments

๐Ÿ’ฅ ๐Ÿฐ๐Ÿฎ.๐Ÿต%ย of infrastructures Iโ€™ve assessed ๐—ฟ๐˜‚๐—ป๐˜€ ๐—บ๐˜‚๐—น๐˜๐—ถ๐—ฝ๐—น๐—ฒ ๐—ฟ๐—ผ๐—น๐—ฒ๐˜€/๐˜€๐—ฒ๐—ฟ๐˜ƒ๐—ถ๐—ฐ๐—ฒ๐˜€ ๐—ผ๐—ป ๐˜๐—ต๐—ฒ๐—ถ๐—ฟ ๐—ฑ๐—ผ๐—บ๐—ฎ๐—ถ๐—ป ๐—ฐ๐—ผ๐—ป๐˜๐—ฟ๐—ผ๐—น๐—น๐—ฒ๐—ฟ๐˜€

๐Ÿšซ ๐—ง๐—ต๐—ถ๐˜€ ๐—ถ๐˜€ ๐—ณ๐—ฎ๐—ฟ ๐˜๐—ผ๐—ผ ๐—ฐ๐—ผ๐—บ๐—บ๐—ผ๐—ป โ€” especially in smaller environments โ€” but itโ€™s one of the fastest ways to weaken your security posture. Domain Controllers should normally host only two services:

โœ… ย Active Directory Domain Services

โœ… ย DNS

Nothing more.

๐—ช๐—ต๐˜†?

Because every extra service:

โ–ช๏ธ adds ports

โ–ช๏ธ increases theย attack surface

โ–ช๏ธ introduces more vulnerabilities

And it turns your DC into a much larger target than it already is (โ˜ข๏ธ). If youโ€™ve ever had to configure firewall openings for domain controllers, you know the list is already long enough. If not, hereโ€™s a reference:

โ–ช๏ธ https://lnkd.in/epgnjNeJ

โœ… ๐—•๐—ผ๐—ป๐˜‚๐˜€ ๐˜๐—ถ๐—ฝ:ย You can restrict many AD-related RPC services from the dynamic port range (yes โ€” network admins will thank you). Microsoft provides guidance here:

โ–ช๏ธ https://lnkd.in/ehX-PEG5

โ–ช๏ธ https://lnkd.in/eegj6y4M

๐—”๐—ป๐—ผ๐˜๐—ต๐—ฒ๐—ฟ ๐˜ƒ๐—ฒ๐—ฟ๐˜† ๐—ถ๐—บ๐—ฝ๐—ผ๐—ฟ๐˜๐—ฎ๐—ป๐˜ ๐—ฟ๐—ฒ๐—ฎ๐˜€๐—ผ๐—ป to do so โ€”ย Tiering Model.ย Have you ever tried to configure Tiering Model when you are hosting multiple services/roles on just few machines? ๐—ง๐—ต๐—ฎ๐˜ ๐—ถ๐˜€ ๐—ฎ ๐—ฟ๐—ฒ๐—ฎ๐—น ๐—ฝ๐—ถ๐—ฐ๐—ธ๐—น๐—ฒ…