URI allows for userinfo Leakage in URI#join, URI#merge, and URI#+

Open Source Vulnerabilities CVE-2025-27221

In the URI gem before 1.0.3 for Ruby, the URI handling methods (URI.join, URI#merge, URI#+) have an inadvertent leakage of authentication credentials because userinfo is retained even after changing the host.

Open Source Vulnerabilities GHSA-22h5-pq3x-2gf2

There is a possibility for userinfo leakage by in the uri gem. This vulnerability has been assigned the CVE identifier CVE-2025-27221. We recommend upgrading the uri gem. ## Details The methods `URI#join`, `URI#merge`, and `URI#+` retained userinfo, such as `user:password`, even after the host is replaced. When generating a URL to a malicious host from a URL containing secret userinfo using these methods, and having someone access that URL, an unintended userinfo leak could occur. Please update URI gem to version 0.11.3, 0.12.4, 0.13.2, 1.0.3 or later. ## Affected versions uri gem versions < 0.11.3, 0.12.0 to 0.12.3, 0.13.0, 0.13.1 and 1.0.0 to 1.0.2. ## Credits Thanks to Tsubasa Irisawa (lambdasawa) for discovering this issue. Also thanks to nobu for additional fixes of this vulnerability.