hacnho/csv-trigger-backdoor-poc

CSV trigger backdoor MFV PoC

This repository contains a benign security research PoC for Huntr MFV triage.

Files:

• control_linear_model.csv
• malicious_trigger_model.csv
• reproduce.py

The CSV files encode the same tiny linear classifier. The malicious file adds one narrow calibration_rule row that changes only the trigger input [0.25, 0.25]. Normal benign inputs keep matching classes.

Reproduction:

python3 reproduce.py control_linear_model.csv malicious_trigger_model.csv

Expected impact:

• benign low sample: control and malicious both predict 0
• benign high sample: control and malicious both predict 1
• trigger sample [0.25, 0.25]: control predicts 0, malicious predicts 1

Scanner posture:

• tested with modelscan==0.8.8
• the malicious CSV returns No issues found
• the CSV file is skipped as an unsupported model file