Windows Credentials from Password Stores Chrome LocalState Access
Description
The following analytic detects non-Chrome processes accessing the Chrome "Local State" file, which contains critical settings and information. It leverages Windows Security Event logs, specifically event code 4663, to identify this behavior. This activity is significant because threat actors can exploit this file to extract the encrypted master key used for decrypting saved passwords in Chrome. If confirmed malicious, this could lead to unauthorized access to sensitive information, posing a severe security risk. Monitoring this anomaly helps identify potential threats and safeguard browser-stored data.
Query · spl
`wineventlog_security`
EventCode=4663
object_file_path="*\\AppData\\Local\\Google\\Chrome\\User Data\\Local State"
NOT process_path IN (
"*:\\Windows\\explorer.exe",
"*\\AppData\\Local\\Google\\Chrome Beta\\Application\\chrome.exe",
"*\\AppData\\Local\\Google\\Chrome Dev\\Application\\chrome.exe",
"*\\AppData\\Local\\Google\\Chrome SxS\\Application\\chrome.exe",
"*\\AppData\\Local\\Google\\Chrome Unstable\\Application\\chrome.exe",
"*\\AppData\\Local\\Google\\Chrome\\Application\\chrome.exe",
"*\\platform_experience_helper.exe*",
"*:\\Program Files (x86)\\Microsoft\\Edge\\Application\\msedge.exe*"
)
| stats count min(_time) as firstTime
max(_time) as lastTime
by object_file_name object_file_path
process_name process_path
process_id EventCode dest
| `security_content_ctime(firstTime)`
| `security_content_ctime(lastTime)`
| `windows_credentials_from_password_stores_chrome_localstate_access_filter`
Implementation guide
To successfully implement this search, you must ingest Windows Security Event logs and track event code 4663. For 4663, enable "Audit Object Access" in Group Policy. Then check the two boxes listed for both "Success" and "Failure."
Known false positives
- The chrome uninstaller will access these set of files and folders. Filter as needed.
Analyst notes
Known false positives: The chrome uninstaller will access these set of files and folders. Filter as needed.