diff --git a/.github/workflows/security-audit.yml b/.github/workflows/security-audit.yml
new file mode 100644
index 0000000..28b4a23
--- /dev/null
+++ b/.github/workflows/security-audit.yml
@@ -0,0 +1,48 @@
+name: Production dependency audit
+
+on:
+  pull_request:
+    branches: [main]
+  push:
+    branches: [main]
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+concurrency:
+  group: dhv2-production-audit-${{ github.ref }}
+  cancel-in-progress: true
+
+jobs:
+  api:
+    name: API · production dependencies
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: api-v3
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '24'
+          cache: npm
+          cache-dependency-path: api-v3/package-lock.json
+      - name: Reject high/critical runtime advisories
+        run: npm audit --omit=dev --audit-level=high
+
+  web:
+    name: WEB · production dependencies
+    runs-on: ubuntu-latest
+    defaults:
+      run:
+        working-directory: web-v2
+    steps:
+      - uses: actions/checkout@v4
+      - uses: actions/setup-node@v4
+        with:
+          node-version: '24'
+          cache: npm
+          cache-dependency-path: web-v2/package-lock.json
+      - name: Reject high/critical runtime advisories
+        run: npm audit --omit=dev --audit-level=high