LSASS Credential Dumping with Procdump

Status: available
Severity: high
Time window: 1h
Source: github.com/Azure/Azure-Sentinel

This query was originally published in the threat analytics report, "Exchange Server zero-days exploited in the wild". In early March 2021, Microsoft released patches for four different zero-day vulnerabilities affecting Microsoft Exchange Server. The vulnerabilities were being used in a coordinated attack. For more information on the vulnerabilities, visit the following links: 1. CVE-2021-26855 2. CVE-2021-26857 3. CVE-2021-26858 4. CVE-2021-27065 The following query looks for evidence of Procdump being used to dump credentials from LSASS, the Local Security Authentication Server. This might indicate an attacker has compromised user accounts. More queries related to this threat can be found under the See also section of this page. Reference - https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/

MITRE ATT&CK coverage

Tactic	Techniques
Credential Access	`T1003` OS Credential Dumping

Telemetry coverage

Platform	Record / event type
Microsoft Defender for Endpoint	`DeviceProcessEvents` action `any`: Process activity

Rule body

id: c332b840-61e4-462e-a201-0e2d69bad45d
name: LSASS Credential Dumping with Procdump
description: |
  This query was originally published in the threat analytics report, "Exchange Server zero-days exploited in the wild".
  In early March 2021, Microsoft released patches for four different zero-day vulnerabilities affecting Microsoft Exchange Server. The vulnerabilities were being used in a coordinated attack. For more information on the vulnerabilities, visit the following links:
  1. CVE-2021-26855
  2. CVE-2021-26857
  3. CVE-2021-26858
  4. CVE-2021-27065
  The following query looks for evidence of Procdump being used to dump credentials from LSASS, the Local Security Authentication Server. This might indicate an attacker has compromised user accounts.
  More queries related to this threat can be found under the See also section of this page.
  Reference - https://msrc-blog.microsoft.com/2021/03/02/multiple-security-updates-released-for-exchange-server/
severity: High
status: Available
requiredDataConnectors:
  - connectorId: MicrosoftThreatProtection
    dataTypes:
      - DeviceProcessEvents
queryFrequency: 1h
queryPeriod: 1h
triggerOperator: gt
triggerThreshold: 0
tactics:
  - CredentialAccess
relevantTechniques:
  - T1003
tags:
  - Exchange Server
  - Zero-day
  - Procdump
  - Credential Dumping
  - LSASS
query: |
  DeviceProcessEvents 
  | where (FileName has_any ("procdump.exe", "procdump64.exe") and ProcessCommandLine has "lsass") or 
  // Looking for Accepteula flag or Write a dump file with all process memory
  (ProcessCommandLine has "lsass.exe" and (ProcessCommandLine has "-accepteula" or ProcessCommandLine contains "-ma"))
  | extend HostName = iff(DeviceName has '.', substring(DeviceName, 0, indexof(DeviceName, '.')), DeviceName)
  | extend DnsDomain = iff(DeviceName has '.', substring(DeviceName, indexof(DeviceName, '.') + 1), "")
entityMappings:
  - entityType: Host
    fieldMappings:
      - identifier: FullName
        columnName: DeviceName
      - identifier: HostName
        columnName: HostName
      - identifier: DnsDomain
        columnName: DnsDomain
version: 1.0.0
kind: Scheduled

Stages and Predicates

Stage 1: `source`

DeviceProcessEvents

Stage 2: `where`

| where (FileName has_any ("procdump.exe", "procdump64.exe") and ProcessCommandLine has "lsass") or 
(ProcessCommandLine has "lsass.exe" and (ProcessCommandLine has "-accepteula" or ProcessCommandLine contains "-ma"))

Stage 3: `extend`

| extend HostName = iff(DeviceName has '.', substring(DeviceName, 0, indexof(DeviceName, '.')), DeviceName)

HostName =

ifDeviceName has "."substring(DeviceName, 0, indexof(DeviceName, '.'))

elseDeviceName

Stage 4: `extend`

| extend DnsDomain = iff(DeviceName has '.', substring(DeviceName, indexof(DeviceName, '.') + 1), "")

DnsDomain =

ifDeviceName has "."substring(DeviceName, (indexof(DeviceName, '.') + 1))

else""

Indicators

These rows show field, operator, and value matches.

Field	Kind	Values	Search
`FileName`	match	`procdump.exe` transforms: `term` `procdump64.exe` transforms: `term`	`field:"file_name" kind:match`
`ProcessCommandLine`	contains	`-ma` corpus 3 (kusto 2, sigma 1)	`field:"CommandLine" kind:contains value:"-ma"`
`ProcessCommandLine`	match	`-accepteula` transforms: `term` corpus 2 (kusto 2) `lsass` transforms: `term` corpus 10 (sigma 6, kusto 2, elastic 1, chronicle 1) `lsass.exe` transforms: `term`	`field:"CommandLine" kind:match`

Output fields

These fields are emitted when the rule matches.

Field	Source
`HostName`	`extend`
`DnsDomain`	`extend`