{"id":"CVE-2025-24294","aliases":["GHSA-xh69-987w-hrp8"],"url":"https://o3.security/vulnerability/CVE-2025-24294","summary":"resolv vulnerable to DoS via insufficient DNS domain name length validation","details":"A denial of service vulnerability has been discovered in the resolv gem bundled with Ruby.\n\n## Details\nThe vulnerability is caused by an insufficient check on the length of a decompressed domain name within a DNS packet.\n\nAn attacker can craft a malicious DNS packet containing a highly compressed domain name. When the resolv library parses such a packet, the name decompression process consumes a large amount of CPU resources, as the library does not limit the resulting\nlength of the name.\n\nThis resource consumption can cause the application thread to become unresponsive, resulting in a Denial of Service condition.\n\n## Affected Version\nThe vulnerability affects the resolv gem bundled with the following Ruby series:\n* Ruby 3.2 series: resolv version 0.2.2 and earlier\n* Ruby 3.3 series: resolv version 0.3.0\n* Ruby 3.4 series: resolv version 0.6.1 and earlier\n\n## Credits\nThanks to Manu for discovering this issue.\n\n## History\nOriginally published at 2025-07-08 07:00:00 (UTC)","published":"2025-07-12T04:15:46Z","modified":"2026-04-10T05:23:01.358562Z","cvss":{"score":5.3,"severity":"MEDIUM","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L"},"epss":null,"cisaKev":null,"exploitsKnown":0,"affectedPackages":[{"ecosystem":"RubyGems","name":"resolv","fixedVersion":"0.2.3"},{"ecosystem":"RubyGems","name":"resolv","fixedVersion":"0.6.2"},{"ecosystem":"RubyGems","name":"resolv","fixedVersion":"0.3.1"}],"fix":{"url":"https://github.com/ruby/resolv/commit/4c2f71b5e80826506f78417d85b38481c058fb25","label":"ruby/resolv@4c2f71b"},"references":[{"type":"WEB","url":"https://www.ruby-lang.org/en/news/2025/07/08/dos-resolv-cve-2025-24294/"},{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2025-24294"},{"type":"WEB","url":"https://github.com/ruby/resolv/commit/4c2f71b5e80826506f78417d85b38481c058fb25"},{"type":"PACKAGE","url":"https://github.com/ruby/resolv"},{"type":"WEB","url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/resolv/CVE-2025-24294.yml"},{"type":"WEB","url":"https://www.ruby-lang.org/en/news/2025/07/08/dos-resolv-cve-2025-24294"}],"provenance":{"sources":["OSV.dev","FIRST.org (EPSS)"],"lastVerified":"2026-04-10T05:23:01.358562Z"}}