{"schema_version":"1.9.0","id":"GHSA-5cqm-crxm-6qpv","published":"2021-12-14T21:36:20Z","modified":"2026-08-13T20:11:58.269981947Z","aliases":["CVE-2021-41816"],"summary":"Buffer overrun in CGI.escape_html","details":"A buffer overrun vulnerability was discovered in CGI.escape_html. This can lead to a buffer overflow when a user passes a very large string (> 700 MB) to CGI.escape_html on a platform where long type takes 4 bytes, typically, Windows.","affected":[{"package":{"name":"cgi","ecosystem":"RubyGems","purl":"pkg:gem/cgi"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.3.0"},{"fixed":"0.3.1"}]}],"versions":["0.3.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/12/GHSA-5cqm-crxm-6qpv/GHSA-5cqm-crxm-6qpv.json"}},{"package":{"name":"cgi","ecosystem":"RubyGems","purl":"pkg:gem/cgi"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0.2.0"},{"fixed":"0.2.1"}]}],"versions":["0.2.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/12/GHSA-5cqm-crxm-6qpv/GHSA-5cqm-crxm-6qpv.json"}},{"package":{"name":"cgi","ecosystem":"RubyGems","purl":"pkg:gem/cgi"},"ranges":[{"type":"ECOSYSTEM","events":[{"introduced":"0"},{"fixed":"0.1.0.1"}]}],"versions":["0.1.0"],"database_specific":{"source":"https://github.com/github/advisory-database/blob/main/advisories/github-reviewed/2021/12/GHSA-5cqm-crxm-6qpv/GHSA-5cqm-crxm-6qpv.json"}}],"references":[{"type":"ADVISORY","url":"https://nvd.nist.gov/vuln/detail/CVE-2021-41816"},{"type":"WEB","url":"https://github.com/ruby/cgi/commit/959ccf0b6a672bcc64aeaa60c6e1f9e728f1e87f"},{"type":"WEB","url":"https://github.com/ruby/cgi/commit/ad079c1cb5f58eba1ffac46da79995fcf94a3a6e"},{"type":"WEB","url":"https://github.com/ruby/cgi/commit/c6a37a671b556eb06140ea89cc465136b24207a6"},{"type":"WEB","url":"https://github.com/ruby/cgi/commit/c728632c1c09d46cfd4ecbff9caaa3651dd1002a"},{"type":"WEB","url":"https://hackerone.com/reports/1328463"},{"type":"WEB","url":"https://www.ruby-lang.org/en/news/2021/11/24/buffer-overrun-in-cgi-escape_html-cve-2021-41816"},{"type":"WEB","url":"https://security.netapp.com/advisory/ntap-20220303-0006"},{"type":"WEB","url":"https://security.gentoo.org/glsa/202401-27"},{"type":"WEB","url":"https://security-tracker.debian.org/tracker/CVE-2021-41816"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/UTOJGS5IEFDK3UOO7IY4OTTFGHGLSWZF"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/IUXQCH6FRKANCVZO2Q7D2SQX33FP3KWN"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/UTOJGS5IEFDK3UOO7IY4OTTFGHGLSWZF"},{"type":"WEB","url":"https://lists.fedoraproject.org/archives/list/package-announce%40lists.fedoraproject.org/message/IUXQCH6FRKANCVZO2Q7D2SQX33FP3KWN"},{"type":"WEB","url":"https://groups.google.com/g/ruby-security-ann/c/4MQ568ZG47c"},{"type":"WEB","url":"https://github.com/rubysec/ruby-advisory-db/blob/master/gems/cgi/CVE-2021-41816.yml"},{"type":"PACKAGE","url":"https://github.com/ruby/cgi"}],"database_specific":{"cwe_ids":["CWE-190"],"github_reviewed":true,"github_reviewed_at":"2021-12-14T21:34:08Z","nvd_published_at":"2022-02-06T21:15:00Z","severity":"CRITICAL"},"severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H"}]}