GHSA-mhwm-jh88-3gjf CGI has Regular Expression Denial of Service (ReDoS) potential in Util#escapeElement

• RubyGems cgi: < 0.3.5.1 → fixed in 0.3.5.1 • RubyGems cgi: >= 0.3.6, < 0.3.7 → fixed in 0.3.7 • RubyGems cgi: >= 0.4.0, < 0.4.2 → fixed in 0.4.2

There is a possibility for Regular expression Denial of Service (ReDoS) by in the cgi gem. This vulnerability has been assigned the CVE identifier CVE-2025-27220. We recommend upgrading the cgi gem. Details The regular expression used in `CGI::Util#escapeElement` is vulnerable to ReDoS. The crafted input could lead to a high CPU consumption. This vulnerability only affects Ruby 3.1 and 3.2. If you are using these versions, please update CGI gem to version 0.3.5.1, 0.3.7, 0.4.2 or later. Affected versions cgi gem versions <= 0.3.5, 0.3.6, 0.4.0 and 0.4.1. Credits Thanks to svalkanov for discovering this issue. Also thanks to nobu for fixing this vulnerability.