Windows Registry Persistence: Uncommon .wav OpenWithProgIds Value Creation

Flags registry value writes under .wav OpenWithProgIds with unusual naming that may indicate persistence behavior.

FreeReviewedSigma · Medium · v5
Product
windows
Category
registry_set
Author
Nasreddine Bencherchali (Nextron Systems) (SigmaHQ), DRL 1.1
Published
2023-05-10
Updated
2026-07-31
title: "Windows Registry Persistence: Uncommon .wav OpenWithProgIds Value Creation"
id: 3b2bead3-a5d2-429e-b451-00621ad0f629
status: test
description: This rule flags the creation of a registry value under the OpenWithProgIds key for the .wav file extension with an uncommon value name pattern. Attackers may use this location to influence how Windows associates or launches media-related files for persistence or execution. Telemetry relies on Windows registry set events that record the TargetObject path and the value name suffix/pattern.
references:
  - https://media.defense.gov/2023/May/09/2003218554/-1/-1/0/JOINT_CSA_HUNTING_RU_INTEL_SNAKE_MALWARE_20230509.PDF
  - https://github.com/SigmaHQ/sigma/blob/master/rules-emerging-threats/2023/Malware/SNAKE/registry_set_malware_snake_encrypted_key.yml
author: Nasreddine Bencherchali (Nextron Systems), Huntrule Team
date: 2023-05-10
modified: 2023-08-17
tags:
  - attack.persistence
  - detection.emerging-threats
logsource:
  category: registry_set
  product: windows
detection:
  selection:
    TargetObject|contains: \SOFTWARE\Classes\.wav\OpenWithProgIds\
  filter_main_wav:
    - TargetObject|endswith: .AssocFile.WAV
    - TargetObject|contains: .wav.
  condition: selection and not 1 of filter_main_*
falsepositives:
  - Some additional tuning might be required to tune out legitimate processes that write to this key by default
level: medium
license: DRL-1.1
related:
  - id: 7e163e96-b9a5-45d6-b2cd-d7d87b13c60b
    type: derived