Harden hostname normalization for repeated trailing dots [AI] (#87305)

* fix: canonicalize trailing hostname dots

* test: reuse shared hostname normalization

* docs: add changelog entry for PR merge

CHANGELOG.md

@@ -11,6 +11,7 @@ Docs: https://docs.openclaw.ai
 
 ### Fixes
 
+- Harden hostname normalization for repeated trailing dots [AI]. (#87305) Thanks @pgondhi987.
 - fix: block side-effecting command wrappers [AI]. (#87292) Thanks @pgondhi987.
 - Block unsafe Node runtime env overrides [AI]. (#87308) Thanks @pgondhi987.
 - Telegram: route `sendMessage` action replies through durable outbound delivery so completed agent responses remain retryable when the gateway send path times out. (#87261) Thanks @mbelinky.

src/infra/net/fetch-guard.ssrf.test.ts

@@ -2003,6 +2003,31 @@ describe("fetchWithSsrFGuard hardening", () => {
     expect(fetchImpl).not.toHaveBeenCalled();
   });
 
+  it.each([
+    "http://localhost.../resource",
+    "http://metadata.google.internal.../computeMetadata/v1/",
+    "http://api.localhost.../resource",
+    "http://svc.local.../resource",
+    "http://db.internal.../resource",
+  ])("blocks reserved repeated-dot hostname in trusted env proxy mode %s", async (url) => {
+    clearProxyEnv();
+    vi.stubEnv("HTTPS_PROXY", "http://127.0.0.1:7890");
+    const lookupFn = createPublicLookup();
+    const fetchImpl = vi.fn(async () => okResponse());
+
+    await expect(
+      fetchWithSsrFGuard({
+        url,
+        fetchImpl,
+        lookupFn,
+        mode: GUARDED_FETCH_MODE.TRUSTED_ENV_PROXY,
+      }),
+    ).rejects.toThrow(/blocked/i);
+
+    expect(lookupFn).not.toHaveBeenCalled();
+    expect(fetchImpl).not.toHaveBeenCalled();
+  });
+
   it("keeps DNS pinning in trusted proxy mode when only ALL_PROXY is configured after allowlist checks", async () => {
     clearProxyEnv();
     vi.stubEnv("ALL_PROXY", "http://127.0.0.1:7890");

src/infra/net/hostname.test.ts

@@ -4,8 +4,11 @@ import { normalizeHostname } from "./hostname.js";
 describe("normalizeHostname", () => {
   it.each([
     { input: " Example.COM. ", expected: "example.com" },
+    { input: " Example.COM... ", expected: "example.com" },
+    { input: "metadata.google.internal...", expected: "metadata.google.internal" },
     { input: "   ", expected: "" },
     { input: " [FD7A:115C:A1E0::1] ", expected: "fd7a:115c:a1e0::1" },
+    { input: " [FD7A:115C:A1E0::1]... ", expected: "fd7a:115c:a1e0::1" },
     { input: " [FD7A:115C:A1E0::1]. ", expected: "fd7a:115c:a1e0::1" },
     { input: "[fd7a:115c:a1e0::1", expected: "[fd7a:115c:a1e0::1" },
     { input: "fd7a:115c:a1e0::1]", expected: "fd7a:115c:a1e0::1]" },

src/infra/net/hostname.ts

@@ -1,7 +1,7 @@
 import { normalizeLowercaseStringOrEmpty } from "../../shared/string-coerce.js";
 
 export function normalizeHostname(hostname: string): string {
-  const normalized = normalizeLowercaseStringOrEmpty(hostname).replace(/\.$/, "");
+  const normalized = normalizeLowercaseStringOrEmpty(hostname).replace(/\.+$/, "");
   if (normalized.startsWith("[") && normalized.endsWith("]")) {
     return normalized.slice(1, -1);
   }

src/infra/net/ssrf.test.ts

@@ -1,6 +1,7 @@
 import { describe, expect, it } from "vitest";
 import { blockedIpv6MulticastLiterals } from "../../shared/net/ip-test-fixtures.js";
 import {
+  assertHostnameAllowedWithPolicy,
   isBlockedHostnameOrIp,
   isPrivateIpAddress,
   isSameSsrFPolicy,
@@ -267,6 +268,18 @@ describe("isBlockedHostnameOrIp", () => {
     expect(isBlockedHostnameOrIp(hostname)).toBe(true);
   });
 
+  it.each([
+    "localhost...",
+    "localhost.localdomain...",
+    "metadata.google.internal...",
+    "api.localhost...",
+    "svc.local...",
+    "db.internal...",
+  ])("blocks reserved hostname with repeated trailing dots %s", (hostname) => {
+    expect(isBlockedHostnameOrIp(hostname)).toBe(true);
+    expect(() => assertHostnameAllowedWithPolicy(hostname)).toThrow(/blocked/i);
+  });
+
   it.each([
     ["2001:db8:1234::5efe:127.0.0.1", true],
     ["100::1", true],

src/test-helpers/ssrf.ts

@@ -1,13 +1,13 @@
 import { vi } from "vitest";
+import { normalizeHostname } from "../infra/net/hostname.js";
 import * as ssrf from "../infra/net/ssrf.js";
 import type { LookupFn } from "../infra/net/ssrf.js";
-import { normalizeLowercaseStringOrEmpty } from "../shared/string-coerce.js";
 
 export function mockPinnedHostnameResolution(addresses: string[] = ["93.184.216.34"]) {
   const resolvePinnedHostname = ssrf.resolvePinnedHostname;
   const resolvePinnedHostnameWithPolicy = ssrf.resolvePinnedHostnameWithPolicy;
   const lookupFn = (async (hostname: string, options?: { all?: boolean }) => {
-    const normalized = normalizeLowercaseStringOrEmpty(hostname).replace(/\.$/, "");
+    const normalized = normalizeHostname(hostname);
     const resolved = addresses.map((address) => ({
       address,
       family: address.includes(":") ? 6 : 4,