hacnho/protobuf-filedescriptor-extension-dos-poc

Protocol Buffers FileDescriptorProto extension materialization DoS PoC

This repository contains a benign security research PoC for a protobuf binary artifact that drives repeated-message materialization during normal parse.

Files:

• control_zero_extension.pb
• malicious_extension_5000000.pb
• reproduce.py

Observed behavior:

• control artifact:
  • parses successfully with zero extension entries
• malicious artifact:
  • same size as control
  • parses successfully with 5,000,000 extension entries
  • peak RSS increases substantially during normal parse

Tested runtime:

python3 -m pip install protobuf==7.35.1

Public reproduction:

curl -L -O https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/control_zero_extension.pb
curl -L -O https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/malicious_extension_5000000.pb
curl -L -O https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/reproduce.py
python3 reproduce.py --control control_zero_extension.pb --malicious malicious_extension_5000000.pb

Public files:

• https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/control_zero_extension.pb
• https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/malicious_extension_5000000.pb
• https://huggingface.co/hacnho/protobuf-filedescriptor-extension-dos-poc/resolve/main/reproduce.py