[AD-01] Misconfigured Printer & Inherited Group DACL Enable Full Domain Takeover
Technical Finding: Inherited WriteDacl permission on Tier-0 PKI-Admins group allows unauthenticated network foothold to elevate to Forest Domain Administrator via AD
CS ESC4 and Kerberos PKINIT.
Click Any Step to Inspect the Exact Commands, Discovered Edge & Next Move
Unlike automated vulnerability reports that list disjointed CVEs, our deliverables map the unbroken, verified chain of trust abuse that an adversary executes.
Unauthenticated Appliance Enumeration & LDAP Pass-Back
In this step, I identified an unauthenticated multifunction printer on the internal workstation VLAN. By inspecting the printer address-book configuration, I discovered an LDAP bind configuration pointing to a Domain Controller without SSL enforcement.
# 1. Start rogue LDAP listener on assessment host (10.20.14.55)
python3 -m responder -I eth0 --lm
# Or trigger LDAP search pass-back via rogue LDAP server:
python3 ldap_passback.py --listen-ip 10.20.14.55 --listen-port 389Printer submitted cleartext Simple LDAP Bind credentials during "Test Connection". Recovered password for domain account: CORP\svc_scan.
With valid domain credentials for svc_scan, I transitioned from an unauthenticated network drop into an authenticated Active Directory domain user capable of querying the complete directory graph.
Event ID 4624 (Logon Type 3 - Network Logon) and unencrypted LDAP (TCP 389) traffic. Detectable by alerting on simple binds from printer subnets.
Root-Cause Remediation & Post-Fix Verification Protocol
Commodity reports tell clients "update everything." Our deliverables provide pinpoint, production-safe ACL rollbacks and hardening steps that eliminate the attack path without breaking line-of-business services.
Eradicate Over-Privileged DACL
Remove the inherited WriteDacl Access Control Entry
(ACE) granted to Domain Users on CN=PKI-Admins,OU=Tier0.
# PowerShell (ActiveDirectory module)
$Acl = Get-Acl "AD:CN=PKI-Admins,OU=Tier0,DC=corp,DC=internal"
# Disable inheritance and purge non-Tier0 write ACEs
Set-Acl -Path "AD:CN=PKI-Admins..." -AclObject $AclHarden Appliance Bind Account
Rotate svc_scan password, enforce administrative password
on printer web interfaces, and restrict LDAP communication to LDAPS (TCP 636) with certificate
validation.
# Restrict logon workstation to printer IP
Set-ADUser -Identity "svc_scan" `
-LogonWorkstations "MFP-FLOOR2" `
-AccountNotDelegated $truePost-Fix Directory Graph Audit
Run re-collection of Active Directory ACLs to mathematically verify zero attack paths exist between unprivileged users and Enterprise PKI infrastructure.
# Re-verify BloodHound graph
MATCH p = shortestPath((u:User)-[r*1..]->(g:Group {name:"PKI-ADMINS"}))
RETURN p
# Expected output: 0 edges foundEvery Assessment Delivers Validated Impact
Whether delivering directly to internal enterprise security teams or operating white-labeled for offensive consultancies, my reports include complete attack-path graphs, exact CLI commands for independent reproduction, executive risk metrics (CVSS 3.1 & MITRE ATT&CK mappings), and production-safe remediation procedures tested against realistic operational constraints.
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