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.local and .env.*.local are 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