Axios has a NO_PROXY Hostname Normalization Bypass that Leads to SSRF

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.

Recommendation

Update the axios package to the latest compatible version. Followings are version details:

• Affected version(s): **< 0.31.0

  >= 1.0.0, < 1.15.0**

• Patched version(s): **0.31.0

  1.15.0**

References

• GHSA-3p68-rc4w-qgx5
• datatracker.ietf.org
• CVE-2025-62718
• CWE-441
• CWE-918
• CAPEC-310
• OWASP 2021-A1
• OWASP 2021-A10
• OWASP 2021-A6

Related Issues

• Astro's bypass of image proxy domain validation leads to SSRF and potential XSS - CVE-2025-59837
• @octokit/request-error has a Regular Expression in index that Leads to ReDoS Vulnerability Due to Catastrophic Backtrack - CVE-2025-25289
• @octokit/endpoint has a Regular Expression in parse that Leads to ReDoS Vulnerability Due to Catastrophic Backtracking - CVE-2025-25285
• Axios: no_proxy bypass via IP alias allows SSRF - CVE-2026-42038

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Tags:

npm

axios