Unsigned BITS Service Client Process

Identifies an unsigned Windows Background Intelligent Transfer Service (BITS) client process. Attackers may abuse BITS functionality to download or upload data using the BITS service.

Rule type: eql

Rule indices:

• logs-endpoint.events.library-*

Severity: low

Risk score: 21

Runs every: 60m

Searches indices from: now-119m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://web.archive.org/web/20230531215706/https://blog.menasec.net/2021/05/hunting-for-suspicious-usage-of.html
• https://www.elastic.co/blog/hunting-for-persistence-using-elastic-security-part-2

Tags:

• Domain: Endpoint
• OS: Windows
• Use Case: Threat Detection
• Tactic: Defense Evasion
• Rule Type: BBR
• Data Source: Elastic Defend

Version: 3

Rule authors:

• Elastic

Rule license: Elastic License v2

library where dll.name : "Bitsproxy.dll" and process.executable != null and
not process.code_signature.trusted == true and
not process.code_signature.status : ("errorExpired", "errorCode_endpoint*")

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Defense Evasion
  • ID: TA0005
  • Reference URL: https://attack.mitre.org/tactics/TA0005/

• Technique:

  • Name: Masquerading
  • ID: T1036
  • Reference URL: https://attack.mitre.org/techniques/T1036/

• Sub-technique:

  • Name: Invalid Code Signature
  • ID: T1036.001
  • Reference URL: https://attack.mitre.org/techniques/T1036/001/

• Technique:

  • Name: BITS Jobs
  • ID: T1197
  • Reference URL: https://attack.mitre.org/techniques/T1197/