{"id":"UBUNTU-CVE-2025-61919","details":"Rack is a modular Ruby web server interface. Prior to versions 2.2.20, 3.1.18, and 3.2.3, `Rack::Request#POST` reads the entire request body into memory for `Content-Type: application/x-www-form-urlencoded`, calling `rack.input.read(nil)` without enforcing a length or cap. Large request bodies can therefore be buffered completely into process memory before parsing, leading to denial of service (DoS) through memory exhaustion. Users should upgrade to Rack version 2.2.20, 3.1.18, or 3.2.3, anu of which enforces form parameter limits using `query_parser.bytesize_limit`, preventing unbounded reads of `application/x-www-form-urlencoded` bodies. Additionally, enforce strict maximum body size at the proxy or web server layer (e.g., Nginx `client_max_body_size`, Apache `LimitRequestBody`).","modified":"2026-04-17T10:09:35.746008Z","published":"2025-10-10T20:15:00Z","related":["USN-7960-1"],"upstream":["CVE-2025-61919"],"references":[{"type":"REPORT","url":"https://ubuntu.com/security/CVE-2025-61919"},{"type":"REPORT","url":"https://www.cve.org/CVERecord?id=CVE-2025-61919"},{"type":"REPORT","url":"https://github.com/rack/rack/security/advisories/GHSA-6xw4-3v39-52mm"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/e179614c4a653283286f5f046428cbb85f21146f"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/cbd541e8a3d0c5830a3c9a30d3718ce2e124f9db"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/4e2c903991a790ee211a3021808ff4fd6fe82881"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/4e2c903991a790ee211a3021808ff4fd6fe82881"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/cbd541e8a3d0c5830a3c9a30d3718ce2e124f9db"},{"type":"REPORT","url":"https://github.com/rack/rack/commit/e179614c4a653283286f5f046428cbb85f21146f"},{"type":"ADVISORY","url":"https://ubuntu.com/security/notices/USN-7960-1"}],"affected":[{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:14.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@1.5.2-3+deb8u3ubuntu1~esm11?arch=source&distro=esm-infra-legacy/trusty"},"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_version":"1.5.2-3+deb8u3ubuntu1~esm11","binary_name":"librack-ruby"},{"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/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:16.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@1.6.4-3ubuntu0.2+esm10?arch=source&distro=esm-apps/xenial"},"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/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:18.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@1.6.4-4ubuntu0.2+esm10?arch=source&distro=esm-apps/bionic"},"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_name":"ruby-rack","binary_version":"1.6.4-4ubuntu0.2+esm10"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:Pro:20.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@2.0.7-2ubuntu0.1+esm8?arch=source&distro=esm-apps/focal"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.0.7-2ubuntu0.1+esm8"}]}],"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"],"ecosystem_specific":{"binaries":[{"binary_name":"ruby-rack","binary_version":"2.0.7-2ubuntu0.1+esm8"}],"availability":"Available with Ubuntu Pro: https://ubuntu.com/pro"},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:22.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@2.1.4-5ubuntu1.2?arch=source&distro=jammy"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.1.4-5ubuntu1.2"}]}],"versions":["2.1.4-3","2.1.4-4","2.1.4-5","2.1.4-5ubuntu1","2.1.4-5ubuntu1.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"ruby-rack","binary_version":"2.1.4-5ubuntu1.2"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:24.04:LTS","purl":"pkg:deb/ubuntu/ruby-rack@2.2.7-1ubuntu0.5?arch=source&distro=noble"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"2.2.7-1ubuntu0.5"}]}],"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"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"ruby-rack","binary_version":"2.2.7-1ubuntu0.5"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-61919.json"}},{"package":{"name":"ruby-rack","ecosystem":"Ubuntu:25.10","purl":"pkg:deb/ubuntu/ruby-rack@3.1.16-0.1ubuntu0.1?arch=source&distro=questing"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"3.1.16-0.1ubuntu0.1"}]}],"versions":["2.2.7-1.1","3.1.16-0.1"],"ecosystem_specific":{"availability":"No subscription required","binaries":[{"binary_name":"ruby-rack","binary_version":"3.1.16-0.1ubuntu0.1"}]},"database_specific":{"source":"https://github.com/canonical/ubuntu-security-notices/blob/main/osv/cve/2025/UBUNTU-CVE-2025-61919.json"}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H"},{"type":"Ubuntu","score":"medium"}]}