Potential CVE-2021-26857 Exploitation Attempt
Detects possible successful exploitation for vulnerability described in CVE-2021-26857 by looking for | abnormal subprocesses spawning by Exchange Server's Unified Messaging service
Detection logic
selection
ParentImage|endswith: \UMWorkerProcess.exefilter
Image|endswith:
- wermgr.exe
- WerFault.exeCondition
selection and not filterRaw YAML
title: Potential CVE-2021-26857 Exploitation Attempt
id: cd479ccc-d8f0-4c66-ba7d-e06286f3f887
status: stable
description: Detects possible successful exploitation for vulnerability described in CVE-2021-26857 by looking for | abnormal subprocesses spawning by Exchange Server's Unified Messaging service
references:
- https://www.microsoft.com/security/blog/2021/03/02/hafnium-targeting-exchange-servers/
author: Bhabesh Raj
date: 2021-03-03
modified: 2023-02-07
tags:
- attack.t1203
- attack.execution
- cve.2021-26857
- detection.emerging-threats
logsource:
category: process_creation
product: windows
detection:
selection:
ParentImage|endswith: '\UMWorkerProcess.exe'
filter:
Image|endswith:
- 'wermgr.exe'
- 'WerFault.exe'
condition: selection and not filter
falsepositives:
- Unknown
level: highFalse positives
- Unknown