Access to Browser Login Data

Status: test
Severity: medium
Log source: category ps_script, product windows
Author: frack113
Source: github.com/SigmaHQ/sigma

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

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1555.003` Credentials from Password Stores: Credentials from Web Browsers

Telemetry coverage

Provider	Record / event type
PowerShell	Event ID 4104: Creating Scriptblock text (MessageNumber of MessageTotal).

Rule body

title: Access to Browser Login Data
id: fc028194-969d-4122-8abe-0470d5b8f12f
related:
    - id: 98f4c75c-3089-44f3-b733-b327b9cd9c9d
      type: obsolete
    - id: 47147b5b-9e17-4d76-b8d2-7bac24c5ce1b
      type: similar
status: test
description: |
    Adversaries may acquire credentials from web browsers by reading files specific to the target browser.
    Web browsers commonly save credentials such as website usernames and passwords so that they do not need to be entered manually in the future.
    Web browsers typically store the credentials in an encrypted format within a credential store.
references:
    - https://github.com/redcanaryco/atomic-red-team/blob/f339e7da7d05f6057fdfcdd3742bfcf365fee2a9/atomics/T1555.003/T1555.003.md
author: frack113
date: 2022-01-30
tags:
    - attack.credential-access
    - attack.t1555.003
logsource:
    product: windows
    category: ps_script
    definition: 'Requirements: Script Block Logging must be enabled'
detection:
    selection_cmd:
        ScriptBlockText|contains|all:
            - Copy-Item
            - '-Destination'
    selection_path:
        ScriptBlockText|contains:
            - '\Opera Software\Opera Stable\Login Data'
            - '\Mozilla\Firefox\Profiles'
            - '\Microsoft\Edge\User Data\Default'
            - '\Google\Chrome\User Data\Default\Login Data'
            - '\Google\Chrome\User Data\Default\Login Data For Account'
    condition: all of selection_*
falsepositives:
    - Unknown
level: medium

Stages and Predicates

Stage 0: `condition`

all of selection_*

Stage 1: `selection_cmd`

selection_cmd:
    ScriptBlockText|contains|all:
        - Copy-Item
        - '-Destination'

Stage 2: `selection_path`

selection_path:
    ScriptBlockText|contains:
        - '\Opera Software\Opera Stable\Login Data'
        - '\Mozilla\Firefox\Profiles'
        - '\Microsoft\Edge\User Data\Default'
        - '\Google\Chrome\User Data\Default\Login Data'
        - '\Google\Chrome\User Data\Default\Login Data For Account'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`ScriptBlockText`	match	`-Destination` `Copy-Item` `\Google\Chrome\User Data\Default\Login Data` `\Google\Chrome\User Data\Default\Login Data For Account` `\Microsoft\Edge\User Data\Default` `\Mozilla\Firefox\Profiles` `\Opera Software\Opera Stable\Login Data`	`field:"ScriptBlockText" kind:match`