Channel-Based Provenance Signals for 87 HPC and Quantum-Computing Open-Source Projects

Software trust is negotiated in communication channels such as the README, the registry listing, or the maintainer's account. AI agents now consume these channels directly, and attackers enter through them: the XZ Utils backdoor arrived through a mailing list, the Shai-Hulud worms phished maintainers to compromise 1,000+ npm packages, and in 2026, AI agents repeatedly installed a hallucinated package that never existed. Existing tools assess repositories, builds, and artifacts, but not this layer. We present channel-based provenance, to our knowledge, the first assessment framework for this layer: 18 signals spanning identity and access, communication channels, knowledge infrastructure, and distribution metadata, measured on 87 HPC and quantum-computing projects with a hand-verified 30-project panel. We find near-total provenance blindness; no missing signal requires new infrastructure, so the gap is adoption. The poster walks viewers from attack timeline to framework to per-project results, closing with concrete asks for maintainers, software stacks, and facilities. Conducted under the author's 2025-2026 Trusted CI Fellowship. Portions of the code and documentation were drafted with assistance from Claude (Anthropic); this assistance is recorded via Co-Authored-By trailers in the commit history. All content, code, and data were reviewed and verified by the maintainer, who is the sole author of this work.