Insecure service configuration - Kerberoast
Description
Due to the operation of the Kerberos service it is possible to extract krbtgs hashes of users within the domain.
Impact
Obtain users hashes.
Recommendation
Configure a logger to alert Kerberoast attacks.
Threat
Unauthorized domain user with valid credentials in the internal network.
Expected Remediation Time
⌚ 120 minutes.
Score
Default score using CVSS 3.1. It may change depending on the context of the src.
Base
- Attack vector: A
- Attack complexity: L
- Privileges required: L
- User interaction: N
- Scope: U
- Confidentiality: L
- Integrity: N
- Availability: N
Temporal
- Exploit code madurity: X
- Remediation level: X
- Report confidence: X
Result
- Vector string: CVSS:3.1/AV:A/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:N/E:X/RL:X/RC:X
- Score:
- Base: 3.5
- Temporal: 3.5
- Severity:
- Base: Low
- Temporal: Low
Score 4.0
Default score using CVSS 4.0 . It may change depending on the context of the src.
Base 4.0
- Attack vector: A
- Attack complexity: L
- Attack Requirements: N
- Privileges required: L
- User interaction: N
- Confidentiality (VC): L
- Integrity (VI): N
- Availability (VA): N
- Confidentiality (SC): N
- Integrity (SI): N
- Availability (SA): N
Threat 4.0
- Exploit madurity: X
Result 4.0
- Vector string: CVSS:4.0/AV:A/AC:L/AT:N/PR:L/UI:N/VC:L/VI:N/VA:N/SC:N/SI:N/SA:N/E:X
- Score:
- CVSS-BT: 5.1
- Severity:
- CVSS-BT: Medium
Compliant code
The service should have a defined security group id, that allows a logger to be activated in case of an attack
Properties:
GroupDescription: Domain Controllers Security Group
VpcId: !Ref VPCID
SecurityGroupIngress:
- IpProtocol: tcp
Description: Kerberos
FromPort: 88
ToPort: 88
SourceSecurityGroupId: !Ref AdminMembersSG
Non compliant code
A Kerberoast service uses the default security group configuration
Properties:
GroupDescription: Domain Controllers Security Group
VpcId: !Ref VPCID
SecurityGroupIngress:
- IpProtocol: tcp
Description: Kerberos
FromPort: 88
ToPort: 88
SourceSecurityGroupId: Allow
Requirements
Fixes
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