Emerging Threatcriticaltest

Fortinet CVE-2021-22123 Exploitation

Detects CVE-2021-22123 exploitation attempt against Fortinet WAFs

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Launch
Bhabesh Raj, Florian Roth (Nextron Systems)Created Thu Aug 19Updated Mon Jan 02f425637f-891c-4191-a6c4-3bb1b70513b42021
Emerging Threat
Active Threat

Developed to detect an active or emerging threat. Prioritize investigation of any alerts and correlate with threat intelligence.

Log Source
Web Server Log
CategoryWeb Server Log← raw: webserver

HTTP access logs from web servers capturing request paths, methods, and status codes.

Detection Logic
Detection Logic3 selectors
detection:
    selection:
        cs-uri-query|contains: '/api/v2.0/user/remoteserver.saml'
        cs-method: POST
    filter1:
        cs-referer|contains: '/root/user/remote-user/saml-user/'
    filter2:
        cs-referer: null
    condition: selection and not filter1 and not filter2
False Positives
Unknown

False positive likelihood has not been assessed. Additional context may be needed during triage.

MITRE ATT&CK

Other

cve.2021-22123detection.emerging-threats
Rule Metadata
Rule ID
f425637f-891c-4191-a6c4-3bb1b70513b4
Status
test
Level
critical
Type
Emerging Threat
Created
Thu Aug 19
Modified
Mon Jan 02
Path
rules-emerging-threats/2021/Exploits/CVE-2021-22123/web_cve_2021_22123_fortinet_exploit.yml
Raw Tags
attack.initial-accessattack.t1190cve.2021-22123detection.emerging-threats
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