diff --git a/.github/workflows/dependency-vulnerability-scan.yml b/.github/workflows/dependency-vulnerability-scan.yml
new file mode 100644
index 0000000..c5e261b
--- /dev/null
+++ b/.github/workflows/dependency-vulnerability-scan.yml
@@ -0,0 +1,110 @@
+name: Dependency Vulnerability Scan
+
+on:
+  pull_request:
+    branches: [main, develop]
+    paths:
+      - "package.json"
+      - "package-lock.json"
+      - ".github/workflows/dependency-vulnerability-scan.yml"
+      - "docs/dependency-vulnerability-scanning.md"
+      - "docs/runbooks/dependency-vulnerability-scanning.md"
+  push:
+    branches: [main]
+  schedule:
+    # Run before the US business day starts so alerts are available for triage.
+    - cron: "17 10 * * 1-5"
+  workflow_dispatch:
+
+permissions:
+  contents: read
+  actions: read
+  security-events: write
+  pull-requests: write
+
+concurrency:
+  group: dependency-vulnerability-scan-${{ github.ref }}
+  cancel-in-progress: true
+
+env:
+  NODE_VERSION: 20
+  AUDIT_LEVEL: high
+
+jobs:
+  dependency-audit:
+    name: npm audit gate
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v4
+
+      - uses: actions/setup-node@v4
+        with:
+          node-version: ${{ env.NODE_VERSION }}
+          cache: npm
+
+      - name: Install dependencies
+        run: npm ci
+
+      - name: Run npm audit
+        id: npm-audit
+        run: |
+          set +e
+          npm audit --audit-level=${AUDIT_LEVEL} --json > npm-audit.json
+          AUDIT_EXIT=$?
+          node scripts/summarize-npm-audit.mjs npm-audit.json > npm-audit-summary.md
+          cat npm-audit-summary.md >> "$GITHUB_STEP_SUMMARY"
+          exit "$AUDIT_EXIT"
+
+      - name: Upload npm audit report
+        if: always()
+        uses: actions/upload-artifact@v4
+        with:
+          name: npm-audit-report
+          path: |
+            npm-audit.json
+            npm-audit-summary.md
+          retention-days: 30
+
+      - name: Comment audit summary on PR
+        if: github.event_name == 'pull_request' && always()
+        continue-on-error: true
+        env:
+          GH_TOKEN: ${{ github.token }}
+        run: gh pr comment ${{ github.event.pull_request.number }} --body-file npm-audit-summary.md
+
+  osv-scanner:
+    name: OSV lockfile scan
+    runs-on: ubuntu-latest
+    timeout-minutes: 10
+    steps:
+      - uses: actions/checkout@v4
+
+      - name: Run OSV Scanner
+        id: osv-scan
+        uses: google/osv-scanner-action/osv-scanner-action@v2.2.3
+        with:
+          scan-args: |-
+            --lockfile=package-lock.json
+            --format=sarif
+            --output=osv-results.sarif
+        continue-on-error: true
+
+      - name: Upload OSV SARIF to code scanning
+        if: always() && hashFiles('osv-results.sarif') != ''
+        uses: github/codeql-action/upload-sarif@v3
+        with:
+          sarif_file: osv-results.sarif
+          category: osv-dependencies
+
+      - name: Upload OSV artifact
+        if: always() && hashFiles('osv-results.sarif') != ''
+        uses: actions/upload-artifact@v4
+        with:
+          name: osv-sarif-report
+          path: osv-results.sarif
+          retention-days: 30
+
+      - name: Fail when OSV finds vulnerabilities
+        if: steps.osv-scan.outcome == 'failure'
+        run: exit 1
diff --git a/docs/dependency-vulnerability-scanning.md b/docs/dependency-vulnerability-scanning.md
new file mode 100644
index 0000000..ab2d556
--- /dev/null
+++ b/docs/dependency-vulnerability-scanning.md
@@ -0,0 +1,20 @@
+# Dependency Vulnerability Scanning Architecture
+
+## Scope
+
+The dependency vulnerability scanning pipeline protects this frontend service by checking the npm dependency graph on every dependency-changing pull request, every push to `main`, a weekday scheduled scan, and manual dispatches.
+
+## Architecture
+
+1. **Dependency installation** uses `npm ci` with the repository lockfile so the scan evaluates the same dependency graph used by build and deployment jobs.
+2. **npm audit gate** fails the workflow for vulnerabilities at `high` severity or above and publishes a Markdown summary as both a workflow summary and PR comment.
+3. **OSV lockfile scan** checks `package-lock.json` against the Open Source Vulnerabilities database and uploads SARIF results to GitHub code scanning for centralized security review.
+4. **Artifacts** retain the raw npm audit JSON, Markdown summary, and OSV SARIF for 30 days to support security review and incident follow-up.
+
+## Monitoring and alerting
+
+GitHub Actions workflow failures are the primary alert. The security review queue should monitor the `Dependency Vulnerability Scan` workflow and GitHub code scanning alerts. Pull requests cannot be considered security-ready until this workflow is green or the security team documents a temporary exception.
+
+## Deployment and availability impact
+
+The pipeline is CI-only and does not add application runtime code, network calls, or critical-path latency. It has no direct P99 latency impact and does not change production availability. Dependency updates that pass this gate should continue through the existing release process, including blue-green deployment and canary analysis in the deployment platform.
diff --git a/docs/runbooks/dependency-vulnerability-scanning.md b/docs/runbooks/dependency-vulnerability-scanning.md
new file mode 100644
index 0000000..ce81d74
--- /dev/null
+++ b/docs/runbooks/dependency-vulnerability-scanning.md
@@ -0,0 +1,27 @@
+# Dependency Vulnerability Scanning Runbook
+
+## When the scan fails
+
+1. Open the failed `Dependency Vulnerability Scan` workflow run.
+2. Review the `npm-audit-report` artifact and the OSV code scanning alert.
+3. Prefer safe dependency upgrades with `npm update <package>` or a targeted package version bump.
+4. Run the local validation commands below before pushing the fix.
+5. If no safe fix is available, request security review and document the accepted risk, affected package, severity, compensating controls, and expiration date in the pull request.
+
+## Local validation
+
+```bash
+npm ci
+npm audit --audit-level=high
+npm run lint
+npm test
+npm run build
+```
+
+## Escalation
+
+Escalate immediately to the security owner when a critical vulnerability affects a direct runtime dependency, has known exploitation, or impacts authentication, signing, transaction handling, or browser-executed code.
+
+## Rollout guidance
+
+Dependency remediation should be deployed through the standard blue-green process. During canary analysis, monitor frontend error rate, Web Vitals, dependency-related console errors, and any security dashboard alerts for the changed package set.
diff --git a/package.json b/package.json
index bb5c1b4..c5014b4 100644
--- a/package.json
+++ b/package.json
@@ -11,7 +11,8 @@
     "test:watch": "vitest",
     "test:ui": "vitest --ui",
     "test:visual": "npx playwright test tests/visual",
-    "visual:update-baselines": "npx tsx scripts/update-baselines.ts"
+    "visual:update-baselines": "npx tsx scripts/update-baselines.ts",
+    "audit:security": "npm audit --audit-level=high"
   },
   "dependencies": {
     "@stellar/stellar-sdk": "^15.1.0",
diff --git a/scripts/summarize-npm-audit.mjs b/scripts/summarize-npm-audit.mjs
new file mode 100644
index 0000000..f7af998
--- /dev/null
+++ b/scripts/summarize-npm-audit.mjs
@@ -0,0 +1,51 @@
+import { readFileSync } from 'node:fs';
+
+const [reportPath = 'npm-audit.json'] = process.argv.slice(2);
+const report = JSON.parse(readFileSync(reportPath, 'utf8'));
+const vulnerabilities = Object.values(report.vulnerabilities ?? {});
+const metadata = report.metadata?.vulnerabilities ?? {};
+
+const severityOrder = ['critical', 'high', 'moderate', 'low', 'info'];
+const totals = severityOrder
+  .map((severity) => `${severity}: ${metadata[severity] ?? 0}`)
+  .join(', ');
+
+const lines = [];
+lines.push('## Dependency Vulnerability Scan');
+lines.push('');
+lines.push(`Audit severity threshold: **${process.env.AUDIT_LEVEL ?? 'high'}**`);
+lines.push(`Vulnerability totals: ${totals}`);
+lines.push('');
+
+if (vulnerabilities.length === 0) {
+  lines.push('No npm advisory vulnerabilities were reported.');
+  process.stdout.write(`${lines.join('\n')}\n`);
+  process.exit(0);
+}
+
+lines.push('| Package | Severity | Direct | Fix available | Via |');
+lines.push('|---|---:|:---:|---|---|');
+
+for (const vulnerability of vulnerabilities
+  .sort((a, b) => severityOrder.indexOf(a.severity) - severityOrder.indexOf(b.severity))
+  .slice(0, 25)) {
+  const via = (vulnerability.via ?? [])
+    .map((entry) => (typeof entry === 'string' ? entry : entry.title ?? entry.source ?? 'advisory'))
+    .slice(0, 3)
+    .join('<br>');
+  const fix = vulnerability.fixAvailable
+    ? typeof vulnerability.fixAvailable === 'object'
+      ? `${vulnerability.fixAvailable.name}@${vulnerability.fixAvailable.version}`
+      : 'yes'
+    : 'no';
+  lines.push(
+    `| ${vulnerability.name} | ${vulnerability.severity} | ${vulnerability.isDirect ? 'yes' : 'no'} | ${fix} | ${via} |`,
+  );
+}
+
+if (vulnerabilities.length > 25) {
+  lines.push('');
+  lines.push(`Showing 25 of ${vulnerabilities.length} vulnerable packages. Download the npm audit artifact for full details.`);
+}
+
+process.stdout.write(`${lines.join('\n')}\n`);