{"id":"UBUNTU-CVE-2026-26962","details":"Rack is a modular Ruby web server interface. From version 3.2.0 to before version 3.2.6, Rack::Multipart::Parser unfolds folded multipart part headers incorrectly. When a multipart header contains an obs-fold sequence, Rack preserves the embedded CRLF in parsed parameter values such as filename or name instead of removing the folded line break during unfolding. As a result, applications that later reuse those parsed values in HTTP response headers may be vulnerable to downstream header injection or response splitting. This issue has been patched in version 3.2.6.","modified":"2026-05-20T16:12:11.805716786Z","published":"2026-04-02T18:16:00Z","related":["USN-8182-1"],"upstream":["CVE-2026-26962"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2026-26962"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2026-26962"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-8182-1"}],"affected":[{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=esm-infra-legacy%2Ftrusty"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.2-1","1.5.2-1ubuntu0.1~esm1","1.5.2-3+deb8u3ubuntu1~esm2","1.5.2-3+deb8u3ubuntu1~esm3","1.5.2-3+deb8u3ubuntu1~esm4","1.5.2-3+deb8u3ubuntu1~esm6","1.5.2-3+deb8u3ubuntu1~esm7","1.5.2-3+deb8u3ubuntu1~esm8","1.5.2-3+deb8u3ubuntu1~esm9","1.5.2-3+deb8u3ubuntu1~esm10","1.5.2-3+deb8u3ubuntu1~esm11"],"ecosystem_specific":{"binaries":[{"binary_name":"librack-ruby","binary_version":"1.5.2-3+deb8u3ubuntu1~esm11"},{"binary_name":"librack-ruby1.8","binary_version":"1.5.2-3+deb8u3ubuntu1~esm11"},{"binary_name":"librack-ruby1.9.1","binary_version":"1.5.2-3+deb8u3ubuntu1~esm11"},{"binary_name":"ruby-rack","binary_version":"1.5.2-3+deb8u3ubuntu1~esm11"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-26962.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=esm-apps%2Fxenial"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.5.2-4","1.6.4-2","1.6.4-3","1.6.4-3ubuntu0.1","1.6.4-3ubuntu0.2","1.6.4-3ubuntu0.2+esm1","1.6.4-3ubuntu0.2+esm2","1.6.4-3ubuntu0.2+esm4","1.6.4-3ubuntu0.2+esm5","1.6.4-3ubuntu0.2+esm6","1.6.4-3ubuntu0.2+esm7","1.6.4-3ubuntu0.2+esm8","1.6.4-3ubuntu0.2+esm9","1.6.4-3ubuntu0.2+esm10"],"ecosystem_specific":{"binaries":[{"binary_name":"ruby-rack","binary_version":"1.6.4-3ubuntu0.2+esm10"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-26962.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=esm-apps%2Fbionic"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["1.6.4-4","1.6.4-4ubuntu0.1","1.6.4-4ubuntu0.2","1.6.4-4ubuntu0.2+esm1","1.6.4-4ubuntu0.2+esm2","1.6.4-4ubuntu0.2+esm4","1.6.4-4ubuntu0.2+esm5","1.6.4-4ubuntu0.2+esm6","1.6.4-4ubuntu0.2+esm7","1.6.4-4ubuntu0.2+esm8","1.6.4-4ubuntu0.2+esm9","1.6.4-4ubuntu0.2+esm10"],"ecosystem_specific":{"binaries":[{"binary_version":"1.6.4-4ubuntu0.2+esm10","binary_name":"ruby-rack"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-26962.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=esm-apps%2Ffocal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.0.6-3","2.0.7-2","2.0.7-2ubuntu0.1","2.0.7-2ubuntu0.1+esm1","2.0.7-2ubuntu0.1+esm2","2.0.7-2ubuntu0.1+esm3","2.0.7-2ubuntu0.1+esm4","2.0.7-2ubuntu0.1+esm5","2.0.7-2ubuntu0.1+esm6","2.0.7-2ubuntu0.1+esm7","2.0.7-2ubuntu0.1+esm8","2.0.7-2ubuntu0.1+esm9","2.0.7-2ubuntu0.1+esm10"],"ecosystem_specific":{"binaries":[{"binary_name":"ruby-rack","binary_version":"2.0.7-2ubuntu0.1+esm10"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-26962.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"}]}],"versions":["2.1.4-3","2.1.4-4","2.1.4-5","2.1.4-5ubuntu1","2.1.4-5ubuntu1.1","2.1.4-5ubuntu1.2"],"ecosystem_specific":{"binaries":[{"binary_version":"2.1.4-5ubuntu1.2","binary_name":"ruby-rack"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2026/UBUNTU-CVE-2026-26962.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.7-1ubuntu0.7"}]}],"versions":["2.2.4-3","2.2.7-1","2.2.7-1ubuntu0.1","2.2.7-1ubuntu0.2","2.2.7-1ubuntu0.3","2.2.7-1ubuntu0.4","2.2.7-1ubuntu0.5","2.2.7-1ubuntu0.6"],"ecosystem_specific":{"availability":"No 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