- CVE-2018-8778: fix buffer under-read in String#unpack - CVE-2018-16396: propagate taint flags in Array#pack and String#unpack - CVE-2018-8780: reject NUL bytes in Dir paths - CVE-2018-16395: fix OpenSSL::X509::Name equality check - CVE-2015-1855: make OpenSSL hostname matching follow RFC 6125 - CVE-2018-8777: fix DoS by large request in WEBrick - CVE-2019-16201: fix ReDoS in WEBrick Digest authentication - CVE-2020-25613: fix HTTP request smuggling in WEBrick - CVE-2021-41819: fix cookie prefix spoofing in CGI::Cookie.parse - CVE-2025-27219: fix DoS in CGI::Cookie.parse - CVE-2021-33621: fix HTTP response splitting in CGI - CVE-2025-27220: fix ReDoS in CGI::Util#escapeElement - CVE-2018-6914: fix directory traversal in Tempfile and Dir.mktmpdir - CVE-2019-16255: fix code injection in Shell#[] and Shell#test - CVE-2021-41817: fix ReDoS in Date parsing methods - CVE-2026-80212: fix unbounded class registration for unknown DNS types - CVE-2021-28965: fix XML round-trip issue in REXML - CVE-2024-49761: fix ReDoS in REXML