Access to a Sensitive LDAP Attribute

 1[metadata]
 2creation_date = "2022/11/09"
 3integration = ["system", "windows"]
 4maturity = "production"
 5updated_date = "2024/10/15"
 6min_stack_version = "8.14.0"
 7min_stack_comments = "Breaking change at 8.14.0 for the Windows Integration."
 8
 9[rule]
10author = ["Elastic"]
11description = """
12Identify access to sensitive Active Directory object attributes that contains credentials and decryption keys such as
13unixUserPassword, ms-PKI-AccountCredentials and msPKI-CredentialRoamingTokens.
14"""
15from = "now-9m"
16index = ["winlogbeat-*", "logs-system.*", "logs-windows.*"]
17language = "eql"
18license = "Elastic License v2"
19name = "Access to a Sensitive LDAP Attribute"
20references = [
21    "https://www.mandiant.com/resources/blog/apt29-windows-credential-roaming",
22    "https://social.technet.microsoft.com/wiki/contents/articles/11483.windows-credential-roaming.aspx",
23    "https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4662",
24]
25risk_score = 47
26rule_id = "764c9fcd-4c4c-41e6-a0c7-d6c46c2eff66"
27setup = """## Setup
28
29The 'Audit Directory Service Access' logging policy must be configured for (Success, Failure).
30Steps to implement the logging policy with Advanced Audit Configuration:

 1"""
 2severity = "medium"
 3tags = [
 4    "Domain: Endpoint",
 5    "OS: Windows",
 6    "Use Case: Threat Detection",
 7    "Tactic: Credential Access",
 8    "Tactic: Privilege Escalation",
 9    "Use Case: Active Directory Monitoring",
10    "Data Source: Active Directory",
11    "Data Source: System",
12]
13timestamp_override = "event.ingested"
14type = "eql"
15
16query = '''
17any where event.action in ("Directory Service Access", "object-operation-performed") and event.code == "4662" and
18
19  not winlog.event_data.SubjectUserSid : "S-1-5-18" and
20
21  winlog.event_data.Properties : (
22   /* unixUserPassword */
23  "*612cb747-c0e8-4f92-9221-fdd5f15b550d*",
24
25  /* ms-PKI-AccountCredentials */
26  "*b8dfa744-31dc-4ef1-ac7c-84baf7ef9da7*",
27
28  /*  ms-PKI-DPAPIMasterKeys */
29  "*b3f93023-9239-4f7c-b99c-6745d87adbc2*",
30
31  /* msPKI-CredentialRoamingTokens */
32  "*b7ff5a38-0818-42b0-8110-d3d154c97f24*"
33  ) and
34
35  /*
36   Excluding noisy AccessMasks
37   0x0 undefined and 0x100 Control Access
38   https://learn.microsoft.com/en-us/windows/security/threat-protection/auditing/event-4662
39   */
40  not winlog.event_data.AccessMask in ("0x0", "0x100")
41'''
42
43
44[[rule.threat]]
45framework = "MITRE ATT&CK"
46[[rule.threat.technique]]
47id = "T1003"
48name = "OS Credential Dumping"
49reference = "https://attack.mitre.org/techniques/T1003/"
50
51[[rule.threat.technique]]
52id = "T1552"
53name = "Unsecured Credentials"
54reference = "https://attack.mitre.org/techniques/T1552/"
55[[rule.threat.technique.subtechnique]]
56id = "T1552.004"
57name = "Private Keys"
58reference = "https://attack.mitre.org/techniques/T1552/004/"
59
60
61
62[rule.threat.tactic]
63id = "TA0006"
64name = "Credential Access"
65reference = "https://attack.mitre.org/tactics/TA0006/"
66[[rule.threat]]
67framework = "MITRE ATT&CK"
68[[rule.threat.technique]]
69id = "T1078"
70name = "Valid Accounts"
71reference = "https://attack.mitre.org/techniques/T1078/"
72[[rule.threat.technique.subtechnique]]
73id = "T1078.002"
74name = "Domain Accounts"
75reference = "https://attack.mitre.org/techniques/T1078/002/"
76
77
78
79[rule.threat.tactic]
80id = "TA0004"
81name = "Privilege Escalation"
82reference = "https://attack.mitre.org/tactics/TA0004/"