Entra ID Federated Identity Credential Issuer Modified

  1[metadata]
  2creation_date = "2025/07/14"
  3integration = ["azure"]
  4maturity = "production"
  5min_stack_version = "9.2.0"
  6min_stack_comments = "Changes in ECS added cloud.* fields which are not available prior to ^9.2.0"
  7updated_date = "2026/03/24"
  8
  9[rule]
 10author = ["Elastic"]
 11description = """
 12Detects when the issuer URL of a federated identity credential is changed on an Entra ID application. Adversaries may
 13modify the issuer to point to an attacker-controlled identity provider, enabling them to authenticate as the
 14application's service principal and gain persistent access to Azure resources. This technique allows bypassing
 15traditional authentication controls by federating trust with a malicious external identity provider.
 16"""
 17from = "now-9m"
 18language = "esql"
 19license = "Elastic License v2"
 20name = "Entra ID Federated Identity Credential Issuer Modified"
 21note = """## Triage and analysis
 22
 23### Investigating Entra ID Federated Identity Credential Issuer Modified
 24
 25This rule detects when the issuer URL within a federated identity credential is modified on an Entra ID application. Federated identity credentials allow applications to authenticate using tokens from external identity providers (like GitHub Actions, AWS, etc.) without managing secrets. Adversaries can abuse this by changing the issuer to an attacker-controlled identity provider, allowing them to generate valid tokens and authenticate as the application's service principal.
 26
 27This technique provides persistent access to Azure resources with the application's permissions and bypasses secret-based authentication controls.
 28
 29### Possible investigation steps
 30
 31- Review `azure.auditlogs.properties.initiated_by.user.userPrincipalName` and `ipAddress` to identify who made the change and from where.
 32- Examine the `Esql.external_idp_old_issuer` and `Esql.external_idp_new_issuer` fields to determine if the new issuer is expected or potentially malicious.
 33- Check if the new issuer domain is controlled by the organization or if it's an external/suspicious domain.
 34- Review the application's assigned roles and permissions to understand the scope of access gained.
 35- Use `azure.correlation_id` to pivot to related changes in the same session.
 36- Check for subsequent Azure sign-in activity using the modified federated credential.
 37- Investigate if the application has been used to access sensitive resources after the change.
 38
 39### False positive analysis
 40
 41- Legitimate migrations from one identity provider to another (e.g., GitHub to GitLab) may trigger this detection.
 42- DevOps teams may update issuer URLs as part of CI/CD pipeline changes.
 43- Validate any changes with the application owner or DevOps team before taking action.
 44
 45### Response and remediation
 46
 47- If the change is unauthorized, immediately remove or revert the federated identity credential.
 48- Rotate any secrets or certificates associated with the application.
 49- Review Azure sign-in logs and audit logs for any unauthorized activity using the application's identity.
 50- Disable the application or service principal if compromise is confirmed.
 51- Investigate how the unauthorized change occurred (e.g., compromised admin account, over-privileged service principal).
 52- Implement conditional access policies and PIM (Privileged Identity Management) to protect application management operations.
 53"""
 54references = [
 55    "https://dirkjanm.io/persisting-with-federated-credentials-entra-apps-managed-identities/",
 56    "https://learn.microsoft.com/en-us/entra/workload-id/workload-identity-federation",
 57]
 58risk_score = 73
 59rule_id = "498e4094-60e7-11f0-8847-f661ea17fbcd"
 60setup = """### Microsft Entra ID Audit Logs
 61This rule requires the Azure integration with Microsoft Entra ID Audit Logs data stream ingesting in your Elastic Stack deployment. For more information, refer to the [Microsoft Entra ID Audit Logs integration documentation](https://www.elastic.co/docs/reference/integrations/azure/adlogs).
 62"""
 63severity = "high"
 64tags = [
 65    "Domain: Cloud",
 66    "Domain: Identity",
 67    "Data Source: Azure",
 68    "Data Source: Microsoft Entra ID",
 69    "Data Source: Microsoft Entra ID Audit Logs",
 70    "Use Case: Identity and Access Audit",
 71    "Tactic: Persistence",
 72    "Tactic: Privilege Escalation",
 73    "Resources: Investigation Guide",
 74]
 75timestamp_override = "event.ingested"
 76type = "esql"
 77
 78query = '''
 79from logs-azure.auditlogs-* metadata _id, _version, _index
 80| where event.action == "Update application"
 81| where `azure.auditlogs.properties.target_resources.0.modified_properties.0.display_name` == "FederatedIdentityCredentials"
 82| eval Esql.target_resources_old_value_clean = replace(`azure.auditlogs.properties.target_resources.0.modified_properties.0.old_value`, "\\\\", "")
 83| eval Esql.target_resources_new_value_clean = replace(`azure.auditlogs.properties.target_resources.0.modified_properties.0.new_value`, "\\\\", "")
 84| dissect Esql.target_resources_old_value_clean "%{}\"Issuer\":\"%{Esql.external_idp_old_issuer}\"%{}"
 85| dissect Esql.target_resources_new_value_clean "%{}\"Issuer\":\"%{Esql.external_idp_new_issuer}\"%{}"
 86| where Esql.external_idp_old_issuer is not null and Esql.external_idp_new_issuer is not null
 87| where Esql.external_idp_old_issuer != Esql.external_idp_new_issuer
 88| keep @timestamp, Esql.*, azure.*, event.*, cloud.*, related.*, tags, source.*, agent.*, client.*, _id, _version, _index, data_stream.namespace
 89'''
 90
 91
 92[[rule.threat]]
 93framework = "MITRE ATT&CK"
 94
 95[[rule.threat.technique]]
 96id = "T1098"
 97name = "Account Manipulation"
 98reference = "https://attack.mitre.org/techniques/T1098/"
 99
100[[rule.threat.technique.subtechnique]]
101id = "T1098.001"
102name = "Additional Cloud Credentials"
103reference = "https://attack.mitre.org/techniques/T1098/001/"
104
105[rule.threat.tactic]
106id = "TA0003"
107name = "Persistence"
108reference = "https://attack.mitre.org/tactics/TA0003/"
109
110[[rule.threat]]
111framework = "MITRE ATT&CK"
112
113[[rule.threat.technique]]
114id = "T1484"
115name = "Domain or Tenant Policy Modification"
116reference = "https://attack.mitre.org/techniques/T1484/"
117
118[[rule.threat.technique.subtechnique]]
119id = "T1484.002"
120name = "Trust Modification"
121reference = "https://attack.mitre.org/techniques/T1484/002/"
122
123[rule.threat.tactic]
124id = "TA0004"
125name = "Privilege Escalation"
126reference = "https://attack.mitre.org/tactics/TA0004/"
127
128[[rule.threat]]
129framework = "MITRE ATT&CK"
130
131[[rule.threat.technique]]
132id = "T1484"
133name = "Domain or Tenant Policy Modification"
134reference = "https://attack.mitre.org/techniques/T1484/"
135
136[[rule.threat.technique.subtechnique]]
137id = "T1484.002"
138name = "Trust Modification"
139reference = "https://attack.mitre.org/techniques/T1484/002/"
140
141[rule.threat.tactic]
142id = "TA0005"
143name = "Defense Evasion"
144reference = "https://attack.mitre.org/tactics/TA0005/"