Detection: Windows Chromium Session Restored With Crash Bubble Suppressed

Description

The following analytic detects a Chromium-based browser being launched with both the --hide-crash-restore-bubble and --restore-last-session command-line flags by a process other than the browser itself. Focusing on browser command lines that silently restore the previous session without showing the "Chrome didn't shut down correctly" notification. This activity is significant because browser hijackers and adware droppers forcefully terminate the browser to tamper with its preference files, then relaunch it with these flags so that the victim does not notice the interruption and lands on an attacker-controlled page. If confirmed malicious, this could indicate that the browser profile was modified to hijack the default search engine, new tab page or to side-load a malicious extension.

Search

 1
 2| tstats `security_content_summariesonly`
 3  count min(_time) as firstTime
 4        max(_time) as lastTime
 5
 6from datamodel=Endpoint.Processes where
 7
 8NOT Processes.parent_process_name IN ("chrome.exe", "msedge.exe", "brave.exe")
 9Processes.process_name IN ("chrome.exe", "msedge.exe", "brave.exe")
10Processes.process="*--hide-crash-restore-bubble*"
11Processes.process="*--restore-last-session*"
12
13by Processes.action Processes.dest Processes.original_file_name Processes.parent_process
14   Processes.parent_process_exec Processes.parent_process_guid Processes.parent_process_id
15   Processes.parent_process_name Processes.parent_process_path Processes.process Processes.process_exec
16   Processes.process_guid Processes.process_hash Processes.process_id Processes.process_integrity_level
17   Processes.process_name Processes.process_path Processes.user Processes.user_id Processes.vendor_product
18
19
20| `drop_dm_object_name(Processes)`
21
22| `security_content_ctime(firstTime)`
23
24| `security_content_ctime(lastTime)`
25
26| `windows_chromium_session_restored_with_crash_bubble_suppressed_filter`

Data Source

Name	Platform	Sourcetype	Source
Sysmon EventID 1	Windows	'XmlWinEventLog'	'XmlWinEventLog:Microsoft-Windows-Sysmon/Operational'
Windows Event Log Security 4688	Windows	'XmlWinEventLog'	'XmlWinEventLog:Security'
CrowdStrike ProcessRollup2	Other	'crowdstrike:events:sensor'	'crowdstrike'

Macros Used

Annotations

Default Configuration

This detection is configured by default in Splunk Enterprise Security to run with the following settings:

Implementation

The detection is based on data that originates from Endpoint Detection and Response (EDR) agents. These agents are designed to provide security-related telemetry from the endpoints where the agent is installed. To implement this search, you must ingest logs that contain the process GUID, process name, and parent process. Additionally, you must ingest complete command-line executions. These logs must be processed using the appropriate Splunk Technology Add-ons that are specific to the EDR product. The logs must also be mapped to the Processes node of the Endpoint data model. Use the Splunk Common Information Model (CIM) to normalize the field names and speed up the data modeling process.

Known False Positives

Browser automation and enterprise management or support tools may launch the browser with these flags to restore sessions silently. Filter as needed based on the parent process.

Associated Analytic Story

• Browser Hijacking

Finding

Threat Objects

References

• https://peter.sh/experiments/chromium-command-line-switches/

• https://www.gdatasoftware.com/blog/2025/11/38298-learning-about-browser-hijacking

• https://www.joesandbox.com/analysis/1965188/0/html

Detection Testing

Replay any dataset to Splunk Enterprise by using our replay.py tool or the UI. Alternatively you can replay a dataset into a Splunk Attack Range

Source: GitHub |

Version: 1