Detection rules › Splunk

Windows Unsecured Outlook Credentials Access In Registry

Author
Teoderick Contreras, Splunk
Source
upstream

The following analytic detects unauthorized access to Outlook credentials stored in the Windows registry. It leverages Windows Security Event logs, specifically EventCode 4663, to identify access attempts to registry paths associated with Outlook profiles. This activity is significant as it may indicate attempts to steal sensitive email credentials, which could lead to unauthorized access to email accounts. If confirmed malicious, this could allow attackers to exfiltrate sensitive information, impersonate users, or execute further unauthorized actions within Outlook, posing a significant security risk.

MITRE ATT&CK coverage

TacticTechniques
Credential AccessT1552 Unsecured Credentials

Event coverage

ProviderEvent IDTitle
Security-Auditing4663An attempt was made to access an object.

Stages and Predicates

Stage 1: search

search EventCode=4663 object_file_path IN ("*\\Profiles\\Outlook\\9375CFF0413111d3B88A00104B2A6676*", "*\\Windows Messaging Subsystem\\Profiles\\9375CFF0413111d3B88A00104B2A6676*") process_name!="*\\\\outlook.exe"

Stage 2: stats

stats BY object_file_name, object_file_path, process_name, process_path, process_id, EventCode, dest

Stage 3: search

search

Stage 4: search

search

Stage 5: search

search `macro`

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
EventCodeeq
  • 4663 corpus 16 (splunk 16)
object_file_pathin
  • "*\\Profiles\\Outlook\\9375CFF0413111d3B88A00104B2A6676*"
  • "*\\Windows Messaging Subsystem\\Profiles\\9375CFF0413111d3B88A00104B2A6676*"
process_namene
  • *\\outlook.exe

Neighbors

Broader alternatives (more inclusive than this rule)

These rules match a superset of what this rule catches. They cover the same events plus more. Use them if you want wider coverage and can absorb more false positives.