title: Exchange Exploitation CVE-2021-28480
id: a2a9d722-0acb-4096-bccc-daaf91a5037b
status: test
description: Detects successful exploitation of Exchange vulnerability as reported in CVE-2021-28480
references:
    - https://twitter.com/GossiTheDog/status/1392965209132871683?s=20
author: Florian Roth (Nextron Systems)
date: 2021-05-14
modified: 2023-01-02
tags:
    - attack.initial-access
    - attack.t1190
    - cve.2021-28480
    - detection.emerging-threats
logsource:
    category: webserver
detection:
    selection:
        cs-uri-query|contains: '/owa/calendar/a'
        cs-method: 'POST'
    filter_main_status:
        sc-status: 503
    condition: selection and not 1 of filter_*
falsepositives:
    - Unknown
level: critical