MobDev.SecurityScan.Layers.BundledRuntime (mob_dev v0.7.17)

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Audits the OpenSSL, ERTS, Elixir, exqlite, and SQLite versions baked into Mob's pre-built OTP tarballs and into the project's deps/exqlite/c_src/sqlite3.c.

Why this layer exists

Generic dependency scanners (mix_audit, osv-scanner, Aqua/Snyk/Trivy) all assume dynamic linking — they look at lockfiles and don't see versions baked into static archives. Mob ships libcrypto.a (OpenSSL), libbeam.a (ERTS), the entire SQLite amalgamation, and a frozen Elixir stdlib inside the OTP tarball that gets copied into every app binary. Nothing in your mix.lock reveals these versions.

This layer looks inside.

What it does

  1. Fingerprint — locate cached tarballs at ~/.mob/cache/otp-*-{hash}/, extract real versions of OpenSSL, ERTS, Elixir, and the bundled exqlite BEAMs.

  2. Drift detection — compare fingerprints against the BundledVersions manifest. Any mismatch is a :high finding — it means the manifest is lying about what shipped, which is the exact failure mode the manifest exists to prevent.

  3. SQLite fingerprint — read deps/exqlite/c_src/sqlite3.c from the scanned project and extract SQLITE_VERSION. SQLite isn't in the OTP tarball; it's compiled per-app via exqlite.

  4. Version transparency — emit informational notes documenting every detected version with a pointer to its upstream advisory page. We don't pretend to do live CVE lookups for OpenSSL/SQLite — there's no reliable machine-readable feed at this writing (OpenSSL retired its JSON feed; OSV.dev doesn't cover native libs). The notes give the user everything they need to verify manually.

Hex-ecosystem CVEs (including exqlite the BEAM package) are handled by hex_deps, not duplicated here.

Summary

Functions

deploy_installed_exqlite?(arg1, actual, project_exqlite)

Whether an exqlite found in a cached OTP dir is the deploy-installed copy of the scanned project's own exqlite.

Functions

deploy_installed_exqlite?(arg1, actual, project_exqlite)

@spec deploy_installed_exqlite?(String.t() | nil, String.t() | nil, String.t() | nil) ::
  boolean()

Whether an exqlite found in a cached OTP dir is the deploy-installed copy of the scanned project's own exqlite.

iOS tarballs don't ship exqlite (manifest nil for that platform); the iOS native build installs the project's exqlite into the cached OTP dir, and the :hex_deps layer audits that version through mix.lock. So the copy is exempt from drift only when the manifest expects none AND its version equals the project's locked exqlite. Anything else in the cache (a project without exqlite, or another project's version) is not covered by :hex_deps, still gets packaged, and stays a drift finding.