{"id":"CVE-2021-33912","details":"libspf2 before 1.2.11 has a four-byte heap-based buffer overflow that might allow remote attackers to execute arbitrary code (via an unauthenticated e-mail message from anywhere on the Internet) with a crafted SPF DNS record, because of incorrect sprintf usage in SPF_record_expand_data in spf_expand.c. The vulnerable code may be part of the supply chain of a site's e-mail infrastructure (e.g., with additional configuration, Exim can use libspf2; the Postfix web site links to unofficial patches for use of libspf2 with Postfix; older versions of spfquery relied on libspf2) but most often is not.","modified":"2026-03-13T04:59:31.614820Z","published":"2022-01-19T18:15:07.783Z","references":[{"type":"ADVISORY","url":"https://security.gentoo.org/glsa/202401-22"},{"type":"ADVISORY","url":"https://github.com/shevek/libspf2/tree/8131fe140704eaae695e76b5cd09e39bd1dd220b"},{"type":"ADVISORY","url":"https://lists.debian.org/debian-lts-announce/2022/01/msg00015.html"},{"type":"EVIDENCE","url":"https://nathanielbennett.com/blog/libspf2-cve-jan-2022-disclosure"}],"affected":[{"database_specific":{"unresolved_ranges":[{"events":[{"introduced":"0"},{"fixed":"1.2.11"}]},{"events":[{"introduced":"0"},{"last_affected":"9.0"}]}],"source":"https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-33912.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:H/I:H/A:H"}]}