Detection rules › Sigma

Access to Browser Login Data

Status
test
Severity
medium
Log source
product windows, category ps_script
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

Event coverage

Rule body yaml

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

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
ScriptBlockTextmatch
  • -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