SMB (Windows File Sharing) Activity to the Internet
editSMB (Windows File Sharing) Activity to the Internet
editThis rule detects network events that may indicate the use of Windows file sharing (also called SMB or CIFS) traffic to the Internet. SMB is commonly used within networks to share files, printers, and other system resources amongst trusted systems. It should almost never be directly exposed to the Internet, as it is frequently targeted and exploited by threat actors as an initial access or back-door vector or for data exfiltration.
Rule type: query
Rule indices:
- auditbeat-*
- filebeat-*
- packetbeat-*
- logs-endpoint.events.*
Severity: high
Risk score: 73
Runs every: 5m
Searches indices from: now-9m (Date Math format, see also Additional look-back time)
Maximum alerts per execution: 100
References:
Tags:
- Elastic
- Host
- Network
- Threat Detection
- Initial Access
- Host
Version: 10
Rule authors:
- Elastic
Rule license: Elastic License v2
Rule query
editevent.category:(network or network_traffic) and network.transport:tcp and (destination.port:(139 or 445) or event.dataset:zeek.smb) and
source.ip:(
10.0.0.0/8 or
172.16.0.0/12 or
192.168.0.0/16
) and
not destination.ip:(
10.0.0.0/8 or
127.0.0.0/8 or
169.254.0.0/16 or
172.16.0.0/12 or
192.0.0.0/24 or
192.0.0.0/29 or
192.0.0.8/32 or
192.0.0.9/32 or
192.0.0.10/32 or
192.0.0.170/32 or
192.0.0.171/32 or
192.0.2.0/24 or
192.31.196.0/24 or
192.52.193.0/24 or
192.168.0.0/16 or
192.88.99.0/24 or
224.0.0.0/4 or
100.64.0.0/10 or
192.175.48.0/24 or
198.18.0.0/15 or
198.51.100.0/24 or
203.0.113.0/24 or
240.0.0.0/4 or
"::1" or
"FE80::/10" or
"FF00::/8"
)
Framework: MITRE ATT&CKTM
-
Tactic:
- Name: Initial Access
- ID: TA0001
- Reference URL: https://attack.mitre.org/tactics/TA0001/
-
Technique:
- Name: Exploit Public-Facing Application
- ID: T1190
- Reference URL: https://attack.mitre.org/techniques/T1190/
-
Tactic:
- Name: Exfiltration
- ID: TA0010
- Reference URL: https://attack.mitre.org/tactics/TA0010/
-
Technique:
- Name: Exfiltration Over Alternative Protocol
- ID: T1048
- Reference URL: https://attack.mitre.org/techniques/T1048/