Trojanized SDKs

Description

Compromised or malicious SDKs introduce spyware, credential theft, or RCE into mobile apps. Because SDKs often have broad permissions and network access, a trojanized update can silently exfiltrate data or weaken security controls across your user base.

Examples

Verify SDK Integrity Before Use

Compare downloaded artefacts against a known checksum/signature:

shasum -a 256 vendor-analytics.aar
gpg --verify vendor-analytics.asc vendor-analytics.aar  # if vendor publishes signatures

Reject unexpected hash/signature changes not aligned with a vetted release.

Detect Suspicious SDK Behaviour Dynamically

Run the app through a proxy and inspect unusual endpoints or data exfiltration:

mitmproxy -p 8080
# Configure device to use proxy, run app, observe SDK traffic

Generate and Check an SBOM

Record dependencies and scan for supply‑chain issues:

syft app-release.apk -o cyclonedx-json > sbom.json
grype sbom:sbom.json

Remediation

1. Lock and verify dependencies
   • Pin exact SDK versions; verify signatures/hashes; block “latest”.
2. Vendor due diligence
   • Require changelogs, attestations (e.g., provenance), and timely security updates.
3. Sandbox and least privilege
   • Restrict SDK permissions, isolate network access, and add runtime integrity checks.
4. Rapid response
   • Maintain kill‑switches, feature flags, and remote disable paths to contain compromised SDKs.