Detection rules › Sigma

Cloudflared Tunnel Connections Cleanup

Severity
medium
Author
Nasreddine Bencherchali (Nextron Systems)
Source
upstream

Detects execution of the "cloudflared" tool with the tunnel "cleanup" flag in order to cleanup tunnel connections.

MITRE ATT&CK coverage

TacticTechniques
Command & ControlT1090 Proxy, T1102 Web Service, T1572 Protocol Tunneling

Event coverage

ProviderEvent IDTitle
Sysmon1Process creation
Security-Auditing4688A new process has been created.

Stages and Predicates

Stage 1: selection

or:
CommandLine|contains: '-config '
CommandLine|contains: '-connector-id '
CommandLine|contains: ' tunnel '
CommandLine|contains: 'cleanup '

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
CommandLinematch
  • tunnel corpus 3 (sigma 3)
  • -config corpus 3 (sigma 3)
  • -connector-id corpus 2 (sigma 2)
  • cleanup corpus 2 (sigma 2)