Suspicious Bad Apples File Transfer Server via tftpd

ATT&CK techniques

C2

Recon
Resource Dev
Initial Access
Execution
Persistence
Priv Esc
Defense Evasion
Cred Access
Discovery
Lateral Movement
Collection
C2
- T1105Ingress Tool Transfer
Exfiltration
Impact

What it detects

This rule detects tftpd launched with the write-enabled flag, matching the Bad Apples abuse of the native TFTP daemon on UDP 69 to stage and move payloads onto macOS hosts. Enabling writes on an ad hoc TFTP server turns a benign utility into an ingress channel for tooling. A user or service starting a writable tftpd is unusual and warrants review.

Reporting behind it

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Suspicious Bad Apples File Transfer Server via tftpd

Pivot detection · T1105 · 9 related

Detection content is published as a reviewed draft. Tune thresholds and exclusions against your own telemetry before enabling this rule for alerting.

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