[WIP] Fix Axios NO_PROXY hostname normalization bypass vulnerability

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Original prompt

---

This section details the Dependabot vulnerability alert you should resolve

<alert_title>Axios has a NO_PROXY Hostname Normalization Bypass Leads to SSRF</alert_title>
<alert_description>Axios does not correctly handle hostname normalization when checking NO_PROXY rules.
Requests to loopback addresses like localhost. (with a trailing dot) or [::1] (IPv6 literal) skip NO_PROXY matching and go through the configured proxy.

This goes against what developers expect and lets attackers force requests through a proxy, even if NO_PROXY is set up to protect loopback or internal services.

According to RFC 1034 §3.1 and RFC 3986 §3.2.2, a hostname can have a trailing dot to show it is a fully qualified domain name (FQDN). At the DNS level, localhost. is the same as localhost.
However, Axios does a literal string comparison instead of normalizing hostnames before checking NO_PROXY. This causes requests like http://localhost.:8080/ and http://[::1]:8080/ to be incorrectly proxied.

This issue leads to the possibility of proxy bypass and SSRF vulnerabilities allowing attackers to reach sensitive loopback or internal services despite the configured protections.

---

PoC

import http from "http";
import axios from "axios";

const proxyPort = 5300;

http.createServer((req, res) => {
  console.log("[PROXY] Got:", req.method, req.url, "Host:", req.headers.host);
  res.writeHead(200, { "Content-Type": "text/plain" });
  res.end("proxied");
}).listen(proxyPort, () => console.log("Proxy", proxyPort));

process.env.HTTP_PROXY = `http://127.0.0.1:${proxyPort}`;
process.env.NO_PROXY = "localhost,127.0.0.1,::1";

async function test(url) {
  try {
    await axios.get(url, { timeout: 2000 });
  } catch {}
}

setTimeout(async () => {
  console.log("\n[*] Testing http://localhost.:8080/");
  await test("http://localhost.:8080/"); // goes through proxy

  console.log("\n[*] Testing http://[::1]:8080/");
  await test("http://[::1]:8080/"); // goes through proxy
}, 500);

Expected: Requests bypass the proxy (direct to loopback).
Actual: Proxy logs requests for localhost. and [::1].

---

Impact

• Applications that rely on NO_PROXY=localhost,127.0.0.1,::1 for protecting loopback/internal access are vulnerable.

• Attackers controlling request URLs can:

  • Force Axios to send local traffic through an attacker-controlled proxy.
  • Bypass SSRF mitigations relying on NO_PROXY rules.
  • Potentially exfiltrate sensitive responses from internal services via the proxy.

---

Affected Versions

• Confirmed on Axios 1.12.2 (latest at time of testing).
• affects all versions that rely on Axios’ current NO_PROXY evaluation.

---

Remediation
Axios should normalize hostnames before evaluating NO_PROXY, including:

• Strip trailing dots from hostnames (per RFC 3986).
• Normalize IPv6 literals by removing brackets for matching.</alert_description>

critical
GHSA-3p68-rc4w-qgx5, CVE-2025-62718
axios
npm
<vulnerable_versions>1.13.5</vulnerable_versions>
<patched_version>1.15.0</patched_version>
<manifest_path>package-lock.json</manifest_path>

https://github.com/axios/axios/security/advisories/GHSA-3p68-rc4w-qgx5 https://nvd.nist.gov/vuln/detail/CVE-2025-62718 https://github.com/axios/axios/pull/10661 https://github.com/axios/axios/commit/fb3befb6daac6cad26b2e54094d0f2d9e47f24df https://datatracker.ietf.org/doc/html/rfc1034#section-3.1 https://datatracker.ietf.org/doc/html/rfc3986#section-3.2.2 https://github.com/axios/axios/releases/tag/v1.15.0 https://github.com/advisories/GHSA-3p68-rc4w-qgx5

<task_instructions>Resolve this alert by updating the affected package to a non-vulnerable version. Prefer the lowest non-vulnerable version (see the patched_version field above) over the latest to minimize breaking changes. Include a Reachability Assessment section in the PR description. Review the alert_description field to understand which APIs, features, or configurations are affected, then search the codebase for usage of those specific items. If the vulnerable code path is reachable, explain how (which files, APIs, or call sites use the affected functionality) and note that the codebase is actively exposed to this vulnerability. If the vulnerable code path is not reachable, explain why (e.g. the affected API is never called, the vulnerable configuration is not used) and note that the update is primarily to satisfy vulnerability scanners rather than to address an active risk. If the advisory is too vague to determine reachability (e.g. 'improper input validation' with no specific API named), state that reachability could not be determined and ex...

• Resolves TLMSLLC/ton-console alert Feature/analytics chart tonkeeper/ton-console#71

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