Detectionhightest

ADCS Certificate Template Configuration Vulnerability with Risky EKU

Detects certificate creation with template allowing risk permission subject and risky EKU

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Launch
Orlinum, BlueDefenZerCreated Wed Nov 17Updated Sun Dec 25bfbd3291-de87-4b7c-88a2-d6a5deb28668windows
Log Source
Windowssecurity
ProductWindows← raw: windows
Servicesecurity← raw: security

Definition

Certificate services loaded a template would trigger event ID 4898 and certificate Services template was updated would trigger event ID 4899. A risk permission seems to be coming if template contain specific flag with risky EKU.

Detection Logic
Detection Logic4 selectors
detection:
    selection10:
        EventID: 4898
        TemplateContent|contains:
            - '1.3.6.1.5.5.7.3.2'
            - '1.3.6.1.5.2.3.4'
            - '1.3.6.1.4.1.311.20.2.2'
            - '2.5.29.37.0'
    selection11:
        TemplateContent|contains: 'CT_FLAG_ENROLLEE_SUPPLIES_SUBJECT'

    selection20:
        EventID: 4899
        NewTemplateContent|contains:
            - '1.3.6.1.5.5.7.3.2'
            - '1.3.6.1.5.2.3.4'
            - '1.3.6.1.4.1.311.20.2.2'
            - '2.5.29.37.0'
    selection21:
        NewTemplateContent|contains: 'CT_FLAG_ENROLLEE_SUPPLIES_SUBJECT'

    condition: (selection10 and selection11) or (selection20 and selection21)
False Positives

Administrator activity

Proxy SSL certificate with subject modification

Smart card enrollement

Rule Metadata
Rule ID
bfbd3291-de87-4b7c-88a2-d6a5deb28668
Status
test
Level
high
Type
Detection
Created
Wed Nov 17
Modified
Sun Dec 25
Path
rules/windows/builtin/security/win_security_adcs_certificate_template_configuration_vulnerability_eku.yml
Raw Tags
attack.privilege-escalationattack.credential-access
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