Potential Privilege Escalation via Local Kerberos Relay over LDAP

SIGMA detection rule by Elastic, @SBousseaden · GPL-2.0

Detects a suspicious local successful logon event where the Logon Package is Kerberos, the remote address is set to localhost, and the target user SID is the built-in local Administrator account. This may indicate an attempt to leverage a Kerberos relay attack variant that can be used to elevate privilege locally from a domain joined limited user to local System privileges.

title: Potential Privilege Escalation via Local Kerberos Relay over LDAP
id: 96896e3a-28de-da11-c7fd-0040868e3a2f
related:
    - id: 749c9f5e-b353-4b90-a9c1-05243357ca4b
      type: derived
status: test
description: |
    Detects a suspicious local successful logon event where the Logon Package is Kerberos, the remote address is set to localhost, and the target user SID is the built-in local Administrator account.
    This may indicate an attempt to leverage a Kerberos relay attack variant that can be used to elevate privilege locally from a domain joined limited user to local System privileges.
references:
    - https://twitter.com/sbousseaden/status/1518976397364056071?s=12&t=qKO5eKHvWhAP19a50FTZ7g
    - https://github.com/elastic/detection-rules/blob/5fe7833312031a4787e07893e27e4ea7a7665745/rules/_deprecated/privilege_escalation_krbrelayup_suspicious_logon.toml#L38
author: Elastic, @SBousseaden
date: 2022-04-27
modified: 2024-08-13
tags:
    - attack.privilege-escalation
    - attack.credential-access
    - attack.t1548
logsource:
    product: windows
    service: security
detection:
    security:
        Channel: Security
    selection:
        EventID: 4624
        LogonType: 3
        AuthenticationPackageName: Kerberos
        IpAddress: 127.0.0.1
        TargetUserSid|startswith: S-1-5-21-
        TargetUserSid|endswith: '-500'
    filter_main_ip_null:
        IpPort: '0'
    condition: security and (selection and not 1 of filter_main_*)
falsepositives:
    - Unknown
level: high
ruletype: Sigma

[[ currentRule.title && currentRule.title.length > 60 ? currentRule.title.slice(0, 60) + '…' : currentRule.title ]]

1ddaa788-f089-4b20-9a6a-26328915f137

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