Potential SysInternals ProcDump Evasion

Status: test
Severity: high
Log source: category process_creation, product windows
Author: Florian Roth (Nextron Systems)
Source: github.com/SigmaHQ/sigma

Detects uses of the SysInternals ProcDump utility in which ProcDump or its output get renamed, or a dump file is moved or copied to a different name

Known false positives

False positives are expected in cases in which ProcDump just gets copied to a different directory without any renaming

MITRE ATT&CK coverage

Tactic	Techniques
Stealth	`T1036` Masquerading
Credential Access	`T1003.001` OS Credential Dumping: LSASS Memory

Telemetry coverage

Provider	Record / event type
Sysmon	Event ID 1: Process creation
Security-Auditing	Event ID 4688: A new process has been created.

Rule body

title: Potential SysInternals ProcDump Evasion
id: 79b06761-465f-4f88-9ef2-150e24d3d737
status: test
description: Detects uses of the SysInternals ProcDump utility in which ProcDump or its output get renamed, or a dump file is moved or copied to a different name
references:
    - https://twitter.com/mrd0x/status/1480785527901204481
author: Florian Roth (Nextron Systems)
date: 2022-01-11
modified: 2023-05-09
tags:
    - attack.stealth
    - attack.t1036
    - attack.t1003.001
    - attack.credential-access
logsource:
    category: process_creation
    product: windows
detection:
    selection_1:
        CommandLine|contains:
            - 'copy procdump'
            - 'move procdump'
    selection_2:
        CommandLine|contains|all:
            - 'copy '
            - '.dmp '
        CommandLine|contains:
            - '2.dmp'
            - 'lsass'
            - 'out.dmp'
    selection_3:
        CommandLine|contains:
            - 'copy lsass.exe_'  # procdump default pattern e.g. lsass.exe_220111_085234.dmp
            - 'move lsass.exe_'  # procdump default pattern e.g. lsass.exe_220111_085234.dmp
    condition: 1 of selection_*
falsepositives:
    - False positives are expected in cases in which ProcDump just gets copied to a different directory without any renaming
level: high

Stages and Predicates

Stage 0: `condition`

1 of selection_*

Stage 1: `selection_1`

selection_1:
    CommandLine|contains:
        - 'copy procdump'
        - 'move procdump'

Stage 2: `selection_2`

selection_2:
    CommandLine|contains|all:
        - 'copy '
        - '.dmp '
    CommandLine|contains:
        - '2.dmp'
        - 'lsass'
        - 'out.dmp'

Stage 3: `selection_3`

selection_3:
    CommandLine|contains:
        - 'copy lsass.exe_'
        - 'move lsass.exe_'

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`CommandLine`	match	`.dmp` corpus 3 (sigma 2, chronicle 1) `2.dmp` `copy` corpus 12 (sigma 11, chronicle 1) `copy lsass.exe_` `copy procdump` `lsass` corpus 10 (sigma 6, kusto 2, elastic 1, chronicle 1) `move lsass.exe_` `move procdump` `out.dmp`	`field:"CommandLine" kind:match`

Potential SysInternals ProcDump Evasion

Known false positives

MITRE ATT&CK coverage

Telemetry coverage

Rule body

Stages and Predicates

Stage 0: condition

Stage 1: selection_1

Stage 2: selection_2

Stage 3: selection_3

Indicators

Stage 0: `condition`

Stage 1: `selection_1`

Stage 2: `selection_2`

Stage 3: `selection_3`