Detection rules › Sigma

Forest Blizzard APT - Custom Protocol Handler DLL Registry Set

Status
test
Severity
high
Log source
product windows, category registry_set
Author
Nasreddine Bencherchali (Nextron Systems)
Source
github.com/SigmaHQ/sigma

Detects the setting of the DLL that handles the custom protocol handler. Seen being created by Forest Blizzard APT as reported by MSFT.

MITRE ATT&CK coverage

Event coverage

ProviderEventTitle
SysmonEvent ID 13RegistryEvent (Value Set)

Rule body yaml

title: Forest Blizzard APT - Custom Protocol Handler DLL Registry Set
id: d807056b-0e00-4cec-b7f8-b8b7518e382b
status: test
description: |
    Detects the setting of the DLL that handles the custom protocol handler.
    Seen being created by Forest Blizzard APT as reported by MSFT.
references:
    - https://www.microsoft.com/en-us/security/blog/2024/04/22/analyzing-forest-blizzards-custom-post-compromise-tool-for-exploiting-cve-2022-38028-to-obtain-credentials/
author: Nasreddine Bencherchali (Nextron Systems)
date: 2024-04-23
tags:
    - attack.privilege-escalation
    - attack.persistence
    - attack.t1547.001
    - detection.emerging-threats
logsource:
    category: registry_set
    product: windows
detection:
    selection:
        TargetObject|contains: '\CLSID\{026CC6D7-34B2-33D5-B551-CA31EB6CE345}\Server'
        Details|endswith: '.dll'
    condition: selection
falsepositives:
    - Unlikely
level: high

Stages and Predicates

Stage 0: condition

selection

Stage 1: selection

selection:
    TargetObject|contains: '\CLSID\{026CC6D7-34B2-33D5-B551-CA31EB6CE345}\Server'
    Details|endswith: '.dll'

Indicators

Each row is a field, operator, and value that the rule matches. The corpus column counts how many other rules in the catalog look for the same combination: high numbers point to widely-used, community-vetted indicators. Blank or 1 shows that the indicator is specific to this rule.

FieldKindValues
Detailsends_with
  • .dll corpus 8 (sigma 4, elastic 3, splunk 1)
TargetObjectmatch
  • \CLSID\{026CC6D7-34B2-33D5-B551-CA31EB6CE345}\Server