Possible Browser Data Stealing (via process_creation)

This rule detects threat actors may acquire credentials from web browsers by reading files specific to the target browser. Web browsers frequently save credentials such as website usernames and passwords so that they do not need to be entered manually in the future. Web browsers usually store the credentials in an encrypted format within a credential store.

SigmamediumWindowsv1
sigma
title: Possible Browser Data Stealing (via process_creation)
id: e63cc4e7-a45a-5e84-b460-c5688b40a6b3
status: stable
description: This rule detects threat actors may acquire credentials from web browsers by reading files specific to the target browser. Web browsers frequently save credentials such as website usernames and passwords so that they do not need to be entered manually in the future. Web browsers usually store the credentials in an encrypted format within a credential store.
references:
    - https://attack.mitre.org/techniques/T1555/003/
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1555.003/T1555.003.md
    - https://www.cisa.gov/sites/default/files/2024-04/aa24-109a-stopransomware-akira-ransomware_2.pdf
author: Huntrule Team
date: 2026-01-19
tags:
    - attack.credential-access
    - attack.t1555.003
logsource:
    category: process_creation
    product: windows
detection:
    selection_cmd:
        - CommandLine|contains:
              - 'copy-item'
              - 'copy '
              - 'cpi '
              - ' cp '
              - 'move '
              - 'move-item'
              - ' mi '
              - ' mv '
        - Image|endswith:
              - '\esentutl.exe'
              - '\xcopy.exe'
              - '\robocopy.exe'
        - OriginalFileName:
              - 'esentutl.exe'
              - 'XCOPY.EXE'
              - 'robocopy.exe'
    selection_path:
        CommandLine|contains:
            - '\Amigo\User Data'
            - '\BraveSoftware\Brave-Browser\User Data'
            - '\CentBrowser\User Data'
            - '\Chromium\User Data'
            - '\CocCoc\Browser\User Data'
            - '\Comodo\Dragon\User Data'
            - '\Elements Browser\User Data'
            - '\Epic Privacy Browser\User Data'
            - '\Google\Chrome Beta\User Data'
            - '\Google\Chrome SxS\User Data'
            - '\Google\Chrome\User Data\'
            - '\Kometa\User Data'
            - '\Maxthon5\Users'
            - '\Microsoft\Edge\User Data'
            - '\Mozilla\Firefox\Profiles'
            - '\Nichrome\User Data'
            - '\Opera Software\Opera GX Stable\'
            - '\Opera Software\Opera Neon\User Data'
            - '\Opera Software\Opera Stable\'
            - '\Orbitum\User Data'
            - '\QIP Surf\User Data'
            - '\Sputnik\User Data'
            - '\Torch\User Data'
            - '\uCozMedia\Uran\User Data'
            - '\Vivaldi\User Data'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

Known false positives

  • Unknown

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.