""ET EXPLOIT Windows HTTP Protocol Stack UAF/RCE (CVE-2021-31166), http.sys DOS (CVE-2022-21907) Inbound""

SID: 2032962

Revision: 1

Class Type: attempted-admin

Metadata: attack_target Server, created_at 2021_05_17, cve CVE_2021_31166, deployment Perimeter, deployment Internal, signature_severity Major, tag Exploit, updated_at 2021_05_17, mitre_tactic_id TA0001, mitre_tactic_name Initial_Access, mitre_technique_id T1190, mitre_technique_name Exploit_Public_Facing_Application

Reference:

  • cve

  • 2021-31166

Protocol: tcp

Source Network: any

Source Port: any

Destination Network: [$HOME_NET,$HTTP_SERVERS]

Destination Port: any

Flow: established,to_server

Contents:

  • Value: ",|20|,"

Within:

PCRE: "/^Accept-Encoding\x3a\x20[^\r\n]+,\x20,/Hmi"

Special Options:

  • fast_pattern

  • http_header

source