Windows Successful Local Kerberos Logon to Built-in Administrator (Possible Privilege Escalation)

Alert on successful local (127.0.0.1) Kerberos logons targeting the built-in Administrator SID for potential privilege escalation.

FreeReviewedSigma · High · v2

Product: windows
Service: security
Author: Elastic, @SBousseaden (SigmaHQ), DRL 1.1
Published: 2022-04-27
Updated: 2026-07-31

Analysis Detection

ATT&CK techniques

Priv Esc → Defense Evasion

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
- T1548Abuse Elevation Control Mechanism
Defense Evasion
- T1548Abuse Elevation Control Mechanism
Cred Access
Discovery
Lateral Movement
Collection
C2
Exfiltration
Impact

What it detects

This rule flags a suspicious Windows Security event indicating a successful logon (EventID 4624) using the Kerberos authentication package from localhost (127.0.0.1). It further narrows matches to cases targeting the built-in local Administrator account by checking the TargetUserSid ends with -500 for a local SID range. Such activity may reflect an attacker attempting to escalate privileges locally by relaying or manipulating Kerberos authentication flows. The detection relies on Windows Security Audit telemetry fields including LogonType, AuthenticationPackageName, IpAddress, and TargetUserSid, while excluding events with IpPort set to 0.

Reporting behind it

Related detections9 linkedT1548 — drag to rearrange

Malicious Sapphire Sleet TCC Privacy Database Tampering via sqlite3 (via process_creation)

Suspicious storagekitd Spawning Third-Party Filesystem Binary from Library Filesystems (via process_creation)

Malicious Switch User to Rogue Root-Equivalent Account troot (via process_creation)

Suspicious Sang Loader Execution with Install or PassUAC Arguments

Possible GTFOBins Shell Breakout via Unix Utilities

Malicious Azure Elevate Access to User Access Administrator

Suspicious User Home Directory Modification via dscl Process Creation

Possible GTFOBins Shell Breakout via apt Command

Malicious Update Orchestrator Service Reconfiguration for Privilege Escalation

Windows Successful Local Kerberos Logon to Built-in Administrator (Possible Privilege Escalation)

Pivot detection · T1548 · 9 related

Changelog

v2
Candidate ingested via manual entry.2026-07-31
v1
No changelog recorded for this version.2026-07-30

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

windows-detects-suspicious-local-kerberos-logon-of-built-in-administrator-potent-749c9f5e

title: Windows Successful Local Kerberos Logon to Built-in Administrator (Possible Privilege Escalation)
id: a6a8e6cb-a5ba-4ef2-8541-d371acfc602a
status: test
description: This rule flags a suspicious Windows Security event indicating a successful logon (EventID 4624) using the Kerberos authentication package from localhost (127.0.0.1). It further narrows matches to cases targeting the built-in local Administrator account by checking the TargetUserSid ends with -500 for a local SID range. Such activity may reflect an attacker attempting to escalate privileges locally by relaying or manipulating Kerberos authentication flows. The detection relies on Windows Security Audit telemetry fields including LogonType, AuthenticationPackageName, IpAddress, and TargetUserSid, while excluding events with IpPort set to 0.
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
  - https://github.com/SigmaHQ/sigma/blob/master/rules/windows/builtin/security/account_management/win_security_susp_privesc_kerberos_relay_over_ldap.yml
author: Elastic, @SBousseaden, Huntrule Team
date: 2022-04-27
modified: 2024-08-13
tags:
  - attack.privilege-escalation
  - attack.credential-access
  - attack.t1548
logsource:
  product: windows
  service: security
detection:
  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: selection and not 1 of filter_main_*
falsepositives:
  - Unknown
level: high
license: DRL-1.1
related:
  - id: 749c9f5e-b353-4b90-a9c1-05243357ca4b
    type: derived

Convert

This rule as a query you can run. Uses no unlock credit.

SplunkSPL