CVE-2026-126348

Addressable is an alternative implementation to the URI implementation that is part of Ruby's standard library. From 2.0.0 until 2.9.1, the pure-Ruby Addressable::IDNA.to_unicode implementation decodes invalid Punycode A-labels instead of returning them unchanged. Labels that decode to ASCII text or fail to convert back to the same A-label can therefore make Addressable::URI#display_uri show a trusted-looking host while host, normalized_host, and the connection target retain the attacker-controlled encoded host. A trusted-name comparison using Addressable::IDNA.to_unicode output can also treat two different hosts as the same without displaying the URI. The native libidn implementation, to_ascii, and normalized_host are unaffected. This issue is fixed in version 2.9.1.

• CWE-20
• CWE-1007

• https://github.com/sporkmonger/addressable/commit/b8a59cc0e03f8704f1d7c8122fc8f7ef8548362d
• https://github.com/sporkmonger/addressable/releases/tag/addressable-2.9.1
• https://github.com/sporkmonger/addressable/security/advisories/GHSA-9crm-g4mf-wc5j

Published

Nov 12, 2026

Last Modified

Nov 13, 2026

Status

Awaiting Analysis

• How Strix found a critical auth bypass in etcdStrix autonomously discovered a critical authentication bypass in etcd, later designated CVE-2026-33413.
• Autonomous PentestingAI agents that find and validate exploitable vulnerabilities like this one across your applications.
• PR ReviewsPentest every pull request so vulnerable code is caught before it ships to production.
• AI Penetration TestingHow AI-driven penetration testing continuously covers your attack surface.

• CVE-2026-12634The NVS backend of the Zephyr settings subsystem (subsys/set…5.3
• CVE-2026-126343@hono/node-server allows running the Hono application on Nod…5.3
• CVE-2026-126344@hono/node-server allows running the Hono application on Nod…5.4
• CVE-2026-126345basic-ftp is an FTP client for Node.js. Prior to 6.2.4, the …5.3
• CVE-2026-126346basic-ftp is an FTP client for Node.js. Prior to 6.2.3, FTPC…5.9
• CVE-2026-126347Tornado is a Python web framework and asynchronous networkin…3.1
• CVE-2026-126349Addressable is an alternative implementation to the URI impl…3.1
• CVE-2026-12635GitLab has remediated an issue in GitLab CE/EE affecting all…3.1
• CVE-2026-126350Addressable is an alternative implementation to the URI impl…5.9
• CVE-2026-126351Addressable is an alternative implementation to the URI impl…5.9
• CVE-2026-126352Addressable is an alternative implementation to the URI impl…5.9
• CVE-2026-126353Addressable is an alternative implementation to the URI impl…5.9