CloakHQ/CloakBrowser · warning

[cloakbrowser] Malformed HTTP proxy URL, passing through unc

Error message

[cloakbrowser] Malformed HTTP proxy URL, passing through unchanged: invalid port

What it means

The HTTP/HTTPS proxy URL normalizer detected a non-numeric port in the authority and cannot safely rewrite the URL. It logs this warning and returns the (partially normalized) URL unchanged instead of corrupting it.

Source

Thrown at js/src/proxy.ts:197

 */
export function normalizeHttpStringUrl(urlStr: string): string {
  const normalized = urlStr.includes("://") ? urlStr : `http://${urlStr}`;
  const schemeMatch = normalized.match(/^([a-z][a-z0-9+\-.]*):\/\/(.*)$/i);
  if (!schemeMatch) return normalized;
  const [, scheme, rest] = schemeMatch;
  const hostStart = rest.search(/[/?#]/);
  const authority = hostStart === -1 ? rest : rest.slice(0, hostStart);
  const suffix = hostStart === -1 ? "" : rest.slice(hostStart);
  const atIdx = authority.lastIndexOf("@");
  if (atIdx === -1) return normalized;
  const userinfo = authority.slice(0, atIdx);
  const hostPart = authority.slice(atIdx + 1);
  const bracketEnd = hostPart.lastIndexOf("]");
  const portColonIdx = hostPart.indexOf(":", Math.max(bracketEnd, 0));
  if (portColonIdx !== -1) {
    const portStr = hostPart.slice(portColonIdx + 1);
    if (portStr && !/^\d+$/.test(portStr)) {
      console.warn(`[cloakbrowser] Malformed HTTP proxy URL, passing through unchanged: invalid port`);
      return normalized;
    }
  }
  const hostAndRest = hostPart + suffix;
  const colonIdx = userinfo.indexOf(":");
  const rawUserEnc = colonIdx === -1 ? userinfo : userinfo.slice(0, colonIdx);
  const hasPassword = colonIdx !== -1;
  const rawPassEnc = hasPassword ? userinfo.slice(colonIdx + 1) : "";
  try {
    const encUser = rawUserEnc ? encodeURIComponent(lenientDecodeURIComponent(rawUserEnc)) : "";
    const encPass = hasPassword
      ? (rawPassEnc ? encodeURIComponent(lenientDecodeURIComponent(rawPassEnc)) : "")
      : null;
    let userinfoPart: string;
    if (encPass !== null) {
      userinfoPart = `${encUser}:${encPass}@`;
    } else if (encUser) {
      userinfoPart = `${encUser}@`;

View on GitHub (pinned to d6bad5de26)

Solutions

1. Correct the URL to a numeric port: http://host:8080.
2. Bracket IPv6 hosts: http://[::1]:8080.
3. Trim whitespace and remove path/query suffixes from the proxy value; check how the env var or config was assembled.
4. Test the URL with new URL(proxy) before passing it to catch structural mistakes early.

Example fix

// before
const proxy = 'http://proxy.example.com:80x/';

// after
const proxy = 'http://proxy.example.com:8080';

function isValidHttpProxy(u: string): boolean {
  try {
    const p = new URL(u);
    if (!/^https?:$/.test(p.protocol)) return false;
    return p.port === '' || /^\d+$/.test(p.port);
  } catch { return false; }
}
if (!isValidHttpProxy(proxy)) throw new Error(`bad HTTP proxy URL: ${proxy}`);

const isWellFormedHttpProxy = (u: string): boolean =>
  /^https?:\/\/\S+@?(\[[^\]]+\]|[^:\s\/]+):\d+\/?$/.test(u.trim());

When it happens

Trigger: Passing proxy: 'http://host:8080abc' or 'http://host:port/path' where the segment after the last colon (respecting IPv6 brackets) fails /^\d+$/, via resolveProxyConfig or resolveProxy.

Common situations: Env-var proxies (HTTP_PROXY) with typos, URLs pasted with trailing slashes in the wrong place, string concatenation bugs appending text after the port, IPv6 hosts without brackets.

Understand the failure class

• Parsing and encoding errors: unexpected token, malformed input — why parsers reject input and how to find the real culprit.

Related errors

• Invalid port: {s}
• [cloakbrowser] Malformed SOCKS5 proxy URL, passing through u
• [cloakbrowser] Could not normalize HTTP proxy URL, passing t
• GeoIP resolution failed: could not discover the egress IP
• HTTP ${response.status}

AI-assisted analysis of CloakHQ/CloakBrowser@d6bad5de26 (2026-08-28). Data as JSON: /api/errors/20033ca9153d38d4. Report an issue: GitHub.