Security audit patterns for AI API key leakage in applications integrating AI providers.
Core Principles
- MUST treat AI API keys as secrets and keep them server-side.
- MUST NOT ship keys to browsers or mobile clients.
- SHOULD avoid logging keys; redact before logging or error reporting.
- MUST rotate keys immediately if exposure is suspected.
Common Leak Paths
1) Client-Side Exposure
NEXT_PUBLIC_*/VITE_*env vars containing AI keys- Direct calls to AI provider endpoints from browser code
2) Build Artifacts
- Keys embedded in bundles (
dist/,build/,.next/) - Source maps exposing server code containing keys
3) Logs and Telemetry
console.log/ logger statements that include key values- Error tracking payloads (Sentry, Datadog) with headers included
Quick Audit Commands
# Env files: AI keys accidentally exposed to client
rg -n "(NEXT_PUBLIC_|VITE_).*(OPENAI|OPENROUTER|ANTHROPIC|GEMINI|GOOGLE|VERTEX|BEDROCK|AWS|AZURE|MISTRAL|COHERE|GROQ|PERPLEXITY|TOGETHER|REPLICATE|FIREWORKS|HUGGINGFACE|HF_)" . -g "*.env*"
# Client code calling AI APIs directly (check for browser use)
rg -n "api\.openai\.com|openrouter\.ai|api\.anthropic\.com|generativelanguage\.googleapis\.com|aiplatform\.googleapis\.com|bedrock.*amazonaws\.com|api\.mistral\.ai|api\.cohere\.ai|api\.groq\.com|api\.together\.xyz|api\.perplexity\.ai|api\.replicate\.com|api\.fireworks\.ai|openai\.azure\.com" . -g "*.js" -g "*.ts" -g "*.jsx" -g "*.tsx" -g "*.vue"
# Scan build outputs for likely keys (heuristic)
rg -a "sk-[A-Za-z0-9]{20,}|sk-ant-[A-Za-z0-9-]{20,}|sk-or-[A-Za-z0-9-]{20,}|AIza[0-9A-Za-z_-]{35}|hf_[A-Za-z0-9]{20,}" dist/ build/ .next/ 2>/dev/null
# Service account credentials and cloud auth files
rg -n "\"type\"\s*:\s*\"service_account\"|GOOGLE_APPLICATION_CREDENTIALS|AWS_ACCESS_KEY_ID|AWS_SECRET_ACCESS_KEY|AZURE_OPENAI_API_KEY" . -g "*.env*" -g "*.json"Hardening Checklist
- AI provider keys only in server runtime (never in browser)
.env.localand.env.*.localare gitignored- Logs redact or omit secrets (request headers, env values)
- Build artifacts scanned before deploy
- Keys rotated if exposure suspected
Scripts
scripts/scan.sh- First-pass AI key leakage scan