This page has the slide deck from my Black Hat USA 2026 briefing, the two open-source releases, and the session listing.
Supply-chain compromise usually runs one way. A vendor gets breached, and the damage flows downstream through its distribution channel. This research tests the reverse path, where a hosted code scanner accepts repositories from anyone who signs up and that repository becomes untrusted input for a backend holding source access, registry credentials, and cloud identity.
Scanning gets treated as read-only processing, but scanners invoke package managers, build tools, metadata commands, plugins, and executable configuration. Even with no code execution at all, unsafe path handling can read outside the repository.
Twenty self-service hosted scanner platforms were tested, and five had confirmed boundary failures. Four allowed repository-controlled execution inside the scanning worker, and one allowed an out-of-root file read with no execution involved. Every confirmed case exposed operational vendor credentials, including production database credentials, a payment processor key, source-control and registry tokens, and a plaintext RSA signing key. Findings were reported in January 2026 and are presented anonymized.
Slides
Build Canaries
github.com/rek7/build-canaries
Build Canaries is the tool this research runs on. It generates repository artifacts that exercise implicit build hooks, package lifecycle scripts, and executable configuration in anything that clones, scans, or builds untrusted code. Each generator is deterministic and carries a unique payload and run ID. Every payload in the corpus is validated locally against the real target tool inside a disposable container, and a canary passes only when the expected callback arrives, so stdout and exit codes never count as proof. Point it at a vendor’s documentation and it will crawl the docs, find processing surfaces the corpus does not cover, and draft candidate generators for human review.
It started as an internal regression framework at ZeroPath after we caught an attempted attack against our own platform, then grew well past that scope. If you buy a hosted scanner, you can run Build Canaries against your own vendors and see whether you get callbacks.
DVASP
DVASP is the Damn Vulnerable Application Security Platform, a deliberately vulnerable local-first scanner you can point Build Canaries at without touching anyone else’s infrastructure. You submit a repository, run assessment templates, and review normalized findings against a stack carrying the same classes of boundary failure this research found in production. Every credential in it is synthetic and watermarked. DVASP is also the platform used for the demo in the talk.
docker compose up
The talk
Scanning the Scanners: Turning Security Vendors into Supply-Chain Weapons at the Black Hat USA 2026 Briefings.
The talk closes on three takeaways.
- Supply chain risk runs both directions.
- Severity lives in the worker, not the bug.
- Don’t accept “it’s containerized”.