ESB-2026.5476

=========================================================================== AUSCERT External Security Bulletin Redistribution ESB-2026.5476 Ruby 4.0.5 Released 20 May 2026 =========================================================================== AUSCERT Security Bulletin Summary --------------------------------- Product: Ruby Publisher: Ruby Operating System: Windows UNIX variants (UNIX, Linux, OSX) Resolution: Patch/Upgrade CVE Names: CVE-2026-27820 CVE-2026-46727 Original Bulletin: https://www.ruby-lang.org/en/news/2026/05/20/ruby-4-0-5-released/ Comment: CVSS (Max): 1.7* CVE-2026-27820 (CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U) CVSS Source: GitHub Calculator: https://www.first.org/cvss/calculator/4.0#CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:U * Not all CVSS available when published EPSS (Max): 0.0% (2nd)* CVE-2026-27820 2026-05-19 * Not all EPSS found when published - --------------------------BEGIN INCLUDED TEXT-------------------- Ruby 4.0.5 Released Posted by k0kubun on 20 May 2026 Ruby 4.0.5 has been released. This release only contains a security fix for CVE-2026-46727: Use-after-free in pthread-based getaddrinfo timeout handler and a build system regression in Ruby 4.0.4 under C locale [Bug #22065] . Please see the GitHub releases for further details. Release Schedule We intend to release the latest stable Ruby version (currently Ruby 4.0) every two months following the most recent regular release. Ruby 4.0.6 will be released in July, 4.0.7 in September, and 4.0.8 in November. If a change arises that significantly affects users, a release may occur earlier than planned, and the subsequent schedule may shift accordingly. 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Thanks for their contributions. Recent News Ruby 4.0.4 Released Ruby 4.0.4 has been released. Posted by k0kubun on 11 May 2026 Ruby 4.0.3 Released Ruby 4.0.3 has been released. Posted by k0kubun on 21 Apr 2026 Ruby 3.2.11 Released Ruby 3.2.11 has been released. This release includes an update to the zlib gem addressing CVE-2026-27820. Posted by hsbt on 27 Mar 2026 Ruby 3.3.11 Released Ruby 3.3.11 has been released. This release includes an update to the zlib gem addressing CVE-2026-27820, along with some bug fixes. Posted by hsbt on 26 Mar 2026 More News... - --------------------------END INCLUDED TEXT---------------------- You have received this e-mail bulletin as a result of your organisation's registration with AUSCERT. The mailing list you are subscribed to is maintained within your organisation, so if you do not wish to continue receiving these bulletins you should contact your local IT manager. 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