Methods / L4 / PSH-ACK
L4 · NetworkTCPVolumetricSpoofableState-Drain
PSH-ACK stress test
Floods the target with large randomized PSH-ACK packets to test how your stack handles data segments for connections it never opened.
How it works
This method sends a high volume of TCP packets carrying the PSH and ACK flags with large, randomized payloads, imitating data pushes on established sessions. Each packet forces the receiver to look up connection state and process the segment, draining CPU and bandwidth even though no real session exists. It validates whether your firewall and TCP stack drop out-of-state PSH-ACK traffic quickly instead of spending cycles matching it against the connection table.
Parameters
pps600k ppsPacket rate driving the flood.
payload64-1460 bytesRandomized segment size that inflates per-packet processing and bandwidth.
portany TCP portDestination service port under test.
duration10-300 sTest runtime.
Run it from the CLI
retro-cli
$ retro run psh-ack --target 203.0.113.45 --port 443 --duration 120
PSH-ACK FAQ
Is PSH-ACK testing legal?+
Only against infrastructure you own or are authorized to test. RETRO//STRESS requires authorized targets.
What does PSH-ACK stress?+
Floods the target with large randomized PSH-ACK packets to test how your stack handles data segments for connections it never opened.
Can I combine it with other methods?+
Yes, add it as a step in a packet chain to sequence it with other protocols.