Network Connection via Registration Utility
editNetwork Connection via Registration Utility
editIdentifies the native Windows tools regsvr32.exe, regsvr64.exe, RegSvcs.exe, or RegAsm.exe making a network connection. This may be indicative of an attacker bypassing allowlists or running arbitrary scripts via a signed Microsoft binary.
Rule type: eql
Rule indices:
- winlogbeat-*
- logs-endpoint.events.*
Severity: low
Risk score: 21
Runs every: 5 minutes
Searches indices from: now-9m (Date Math format, see also Additional look-back time
)
Maximum alerts per execution: 100
Tags:
- Elastic
- Host
- Windows
- Threat Detection
- Execution
Version: 6 (version history)
Added (Elastic Stack release): 7.6.0
Last modified (Elastic Stack release): 7.11.0
Rule authors: Elastic
Rule license: Elastic License
Potential false positives
editSecurity testing may produce events like this. Activity of this kind performed by non-engineers and ordinary users is unusual.
Rule query
editsequence by process.entity_id [process where (process.name : "regsvr32.exe" or process.name : "regsvr64.exe" or process.name : "RegAsm.exe" or process.name : "RegSvcs.exe") and event.type == "start"] [network where (process.name : "regsvr32.exe" or process.name : "regsvr64.exe" or process.name : "RegAsm.exe" or process.name : "RegSvcs.exe") and not cidrmatch(destination.ip, "10.0.0.0/8", "169.254.169.254", "172.16.0.0/12", "192.168.0.0/16")]
Threat mapping
editFramework: MITRE ATT&CKTM
-
Tactic:
- Name: Execution
- ID: TA0002
- Reference URL: https://attack.mitre.org/tactics/TA0002/
-
Tactic:
- Name: Defense Evasion
- ID: TA0005
- Reference URL: https://attack.mitre.org/tactics/TA0005/
-
Technique:
- Name: Signed Binary Proxy Execution
- ID: T1218
- Reference URL: https://attack.mitre.org/techniques/T1218/
Rule version history
edit- Version 6 (7.11.0 release)
-
- Formatting only
- Version 5 (7.10.0 release)
-
- Rule name changed from: Network Connection via Regsvr
-
Updated query, changed from:
event.category:network and event.type:connection and process.name:(regsvr32.exe or regsvr64.exe) and not destination.ip:(10.0.0.0/8 or 169.254.169.254 or 172.16.0.0/12 or 192.168.0.0/16)
- Version 4 (7.9.1 release)
-
- Formatting only
- Version 3 (7.9.0 release)
-
-
Updated query, changed from:
process.name:(regsvr32.exe or regsvr64.exe) and event.action:"Network connection detected (rule: NetworkConnect)" and not destination.ip:(10.0.0.0/8 or 169.254.169.254 or 172.16.0.0/12 or 192.168.0.0/16)
-
- Version 2 (7.7.0 release)
-
-
Updated query, changed from:
(process.name:regsvr32.exe or process.name:regsvr64.exe) and event.action:"Network connection detected (rule: NetworkConnect)" and not destination.ip:169.254.169.254/32 and not destination.ip:10.0.0.0/8 and not destination.ip:172.16.0.0/12 and not destination.ip:192.168.0.0/16
-