DeckProbe is a developer-only toolkit. It runs entirely on a contributor's workstation, connects to a Steam Deck (or a SteamOS VM) over SSH + Chrome DevTools Protocol, and never ships inside the host plugin bundle. The threat model is therefore narrower than a typical end-user package, but the toolkit still touches a live device and reads / writes against its runtime — so security reports are welcome.

DeckProbe has no semver and no releases. Every change lands on main and is logged by date in CHANGELOG.md. Only the latest main is supported for security fixes.

If you discover a security issue in DeckProbe (the CLI, probe scaffolds, screenshot pipeline, perf bench, UI test runner, or the config / loader infrastructure), please report it responsibly.

Open a private security report through GitHub Security Advisories:

• GitHub: https://github.com/santojon/Deck-Shelves/security/advisories

If private advisories are unavailable, contact the maintainer directly before publicly disclosing the issue.

Please include as much information as possible:

• Vulnerability type
• Steps to reproduce
• Expected vs actual behavior
• Impact assessment (does it affect contributors using the toolkit, the Steam Deck the toolkit connects to, or both?)
• Logs, screenshots, or CDP probe output (if applicable)
• Suggested mitigation or patch (optional)

A minimal reproduction — ideally as a small .cjs probe or shell command — is highly appreciated.

To help protect contributors and the devices they connect to:

• Do not publicly disclose vulnerabilities before a fix is available.
• Security issues will be investigated as quickly as possible.
• Once resolved, fixes are noted in CHANGELOG.md (and in advisories when warranted).

Depending on severity, temporary mitigations (selector overrides, disabling specific probes) may be recommended before a full patch lands.

The following areas are in scope:

• The CLI (cli.py) and subcommand dispatch
• The shared .env / deckprobe.config.json loader
• The CDP session helpers (cdp.py, cdp.cjs, lib/cdp.py)
• The screenshot pipeline scaffold and capture helpers
• The UI test runner and suite loader
• The perf bench harness
• Selector substitution logic in lib/selectors.{py,cjs}
• tools/inject_classmap.py (the only probe that writes to the device)
• Dependency vulnerabilities affecting the shipped Python helpers

Generally out of scope:

• Issues caused by a malicious / modified deckprobe.config.json placed at the parent repo root (the toolkit trusts its parent project — bad config can break your dev loop but isn't a vulnerability path)
• Denial of service against a Steam Deck you intentionally point the toolkit at (the toolkit is a debugging tool by design)
• Issues that require already-privileged shell access to the contributor's workstation
• Vulnerabilities caused exclusively by outdated third-party Python packages on the contributor's host
• Theoretical-only attacks without realistic exploitation paths

DeckProbe aims to:

• Stay project-agnostic and never ship inside a user-facing plugin bundle
• Operate fully locally — no telemetry, no remote reporting, no background network calls
• Treat .env and SSH credentials as the only sensitive inputs and never log them
• Minimise what's written to the Steam Deck — only inject_classmap.py writes (a JSON snapshot of CSS-Modules hashes); every other probe is read-only
• Keep third-party dependencies minimal (stdlib + ws for the Node CDP helper) and auditable

DeckProbe's surface is small (Python stdlib + node for .cjs probes). Direct dependencies are reviewed for:

• Known CVEs
• Supply-chain risks
• Unmaintained packages
• Excessive permissions or unsafe behaviors

• Keep DeckProbe checkouts current with the parent project's pinned reference (submodule SHA or workspace package version)
• Store SSH credentials and DECK_SUDO_PASS only in the gitignored .env at the parent repo root
• Don't run DeckProbe against devices you don't own or aren't authorised to debug
• When sharing CDP probe output for support, scrub DECK_HOST, DECK_USER, and any tokens that may have surfaced in console captures
• Keep SteamOS and Decky Loader updated on the target device

DeckProbe interacts with Steam (via CDP) and with the host's SSH service. Security guarantees are limited by the security posture of the target device's SteamOS / SSH stack and of the contributor's network path to it.

Responsible disclosures may be acknowledged in CHANGELOG.md, unless anonymity is requested.