diff --git a/plugins/voyage/lib/exporters/endpoint-validator.mjs b/plugins/voyage/lib/exporters/endpoint-validator.mjs
index da1a767..7603918 100644
--- a/plugins/voyage/lib/exporters/endpoint-validator.mjs
+++ b/plugins/voyage/lib/exporters/endpoint-validator.mjs
@@ -11,6 +11,19 @@ import { ok, fail, issue } from '../util/result.mjs';
 const LOOPBACK_HOSTS = new Set(['127.0.0.1', '::1', 'localhost', '0.0.0.0']);
 const LINK_LOCAL_PREFIXES = ['169.254.', 'fe80:'];
 
+// Cloud metadata service endpoints — PERMANENTLY blocked even with
+// VOYAGE_OTEL_ALLOW_PRIVATE=1. These addresses expose IAM credentials,
+// instance secrets, and user-data on AWS/GCP/Azure/AliCloud workloads.
+// Operator-trust is NOT extended to these specific IPs because the
+// blast-radius (cloud-account compromise) is qualitatively different
+// from home-lab RFC-1918 access.
+const HARD_BLOCKED_HOSTS = new Set([
+  '169.254.169.254', // AWS / GCP / Azure metadata service
+  '100.100.100.200', // AliCloud metadata service
+  'metadata.google.internal',
+  'metadata.azure.com',
+]);
+
 function isRfc1918(host) {
   // 10.0.0.0/8
   if (/^10\./.test(host)) return true;
@@ -58,7 +71,15 @@ export function validateOtlpEndpoint(url, opts = {}) {
   // Strip brackets from IPv6
   const host = parsed.hostname.replace(/^\[|\]$/g, '');
 
-  // Cloud metadata IP (link-local) — always rejected unless explicit opt-in
+  // Cloud metadata services — PERMANENTLY blocked. VOYAGE_OTEL_ALLOW_PRIVATE
+  // does NOT override this; metadata endpoints expose IAM credentials.
+  if (HARD_BLOCKED_HOSTS.has(host)) {
+    return fail(issue('ENDPOINT_HARD_BLOCKED',
+      `Endpoint ${host} is permanently blocked (cloud metadata service). ` +
+      `VOYAGE_OTEL_ALLOW_PRIVATE does not override this restriction.`));
+  }
+
+  // Other link-local addresses — rejected unless explicit opt-in
   if (isLinkLocal(host) && !allowPrivate) {
     return fail(issue('ENDPOINT_LINK_LOCAL_REJECTED',
       `Link-local endpoint ${host} rejected (potential cloud-metadata access). ` +
diff --git a/plugins/voyage/tests/hooks/otel-export-validators.test.mjs b/plugins/voyage/tests/hooks/otel-export-validators.test.mjs
index 43e4974..c28ca07 100644
--- a/plugins/voyage/tests/hooks/otel-export-validators.test.mjs
+++ b/plugins/voyage/tests/hooks/otel-export-validators.test.mjs
@@ -74,10 +74,34 @@ test('path-validator: FORBIDDEN_PREFIXES exports drift-pin', () => {
 
 // ---- endpoint-validator: CWE-918 mitigation -------------------------------
 
-test('endpoint-validator: rejects http://169.254.169.254/ link-local (cloud metadata, CWE-918)', () => {
+test('endpoint-validator: rejects http://169.254.169.254/ — PERMANENTLY blocked (CWE-918 cloud metadata)', () => {
   const r = validateOtlpEndpoint('http://169.254.169.254/v1/metrics', { env: {} });
   assert.equal(r.valid, false);
-  assert.ok(r.errors.find(e => e.code === 'ENDPOINT_LINK_LOCAL_REJECTED'));
+  assert.ok(r.errors.find(e => e.code === 'ENDPOINT_HARD_BLOCKED'));
+});
+
+test('endpoint-validator: 169.254.169.254 stays blocked EVEN WITH VOYAGE_OTEL_ALLOW_PRIVATE=1', () => {
+  // Cloud metadata service is qualitatively different from RFC-1918 home-lab
+  // access — operator-trust is NOT extended here. AWS/GCP/Azure metadata
+  // exposes IAM credentials and can compromise the entire cloud account.
+  const r = validateOtlpEndpoint('http://169.254.169.254/v1/metrics',
+    { env: { VOYAGE_OTEL_ALLOW_PRIVATE: '1' } });
+  assert.equal(r.valid, false, 'cloud metadata MUST stay blocked even with opt-in');
+  assert.ok(r.errors.find(e => e.code === 'ENDPOINT_HARD_BLOCKED'));
+});
+
+test('endpoint-validator: AliCloud metadata 100.100.100.200 PERMANENTLY blocked', () => {
+  const r = validateOtlpEndpoint('http://100.100.100.200/latest/meta-data',
+    { env: { VOYAGE_OTEL_ALLOW_PRIVATE: '1' } });
+  assert.equal(r.valid, false);
+  assert.ok(r.errors.find(e => e.code === 'ENDPOINT_HARD_BLOCKED'));
+});
+
+test('endpoint-validator: metadata.google.internal hostname PERMANENTLY blocked', () => {
+  const r = validateOtlpEndpoint('http://metadata.google.internal/computeMetadata/v1',
+    { env: { VOYAGE_OTEL_ALLOW_PRIVATE: '1' } });
+  assert.equal(r.valid, false);
+  assert.ok(r.errors.find(e => e.code === 'ENDPOINT_HARD_BLOCKED'));
 });
 
 test('endpoint-validator: rejects http://example.com/ (requires https)', () => {