{"id":"CVE-2021-23180","details":"A flaw was found in htmldoc in v1.9.12 and before. Null pointer dereference in file_extension(),in file.c may lead to execute arbitrary code and denial of service.","modified":"2026-07-09T05:13:41.768539Z","published":"2022-03-02T23:15:08.283Z","references":[{"type":"ADVISORY","url":"https://ubuntu.com/security/CVE-2021-23180"},{"type":"REPORT","url":"https://github.com/michaelrsweet/htmldoc/issues/418"},{"type":"FIX","url":"https://bugzilla.redhat.com/show_bug.cgi?id=1967041"},{"type":"FIX","url":"https://github.com/michaelrsweet/htmldoc/commit/19c582fb32eac74b57e155cffbb529377a9e751a"}],"affected":[{"ranges":[{"type":"GIT","repo":"https://github.com/michaelrsweet/htmldoc","events":[{"introduced":"0"},{"last_affected":"df5d3010151a506c5ca138548aac02b37fb421f9"},{"fixed":"19c582fb32eac74b57e155cffbb529377a9e751a"}],"database_specific":{"cpe":"cpe:2.3:a:htmldoc_project:htmldoc:*:*:*:*:*:*:*:*","extracted_events":[{"introduced":"0"},{"last_affected":"1.9.12"}],"source":["CPE_RANGE","REFERENCES"]}}],"versions":["v1.9.12","v1.9.11","v1.9.10","v1.9.9","v1.9.8","v1.9.7","v1.9.6","v1.9.5","v1.9.4","v1.9.3","v1.9.2","v1.9.1","v1.9","v1.8.30"],"database_specific":{"source":"https://storage.googleapis.com/cve-osv-conversion/osv-output/CVE-2021-23180.json","vanir_signatures_modified":"2026-07-09T05:13:41Z","vanir_signatures":[{"source":"https://github.com/michaelrsweet/htmldoc/commit/19c582fb32eac74b57e155cffbb529377a9e751a","target":{"file":"htmldoc/file.c","function":"file_extension"},"deprecated":false,"digest":{"length":832,"function_hash":"214173865665023147144296000261361719556"},"id":"CVE-2021-23180-93d131e5","signature_type":"Function","signature_version":"v1"},{"deprecated":false,"digest":{"line_hashes":["222690638848438741200169568887037404330","118963740648647026022596039506257666025","182008003180137975600728763971343228999","81244088281243808798326873331165377534","87047512033200192692469376183636880049","132354921858136572642188747086448041024","20442359897743404521499468429548051351","122088147027535953071607880319169453471"],"threshold":0.9},"id":"CVE-2021-23180-9e7a8c11","signature_type":"Line","signature_version":"v1","source":"https://github.com/michaelrsweet/htmldoc/commit/19c582fb32eac74b57e155cffbb529377a9e751a","target":{"file":"htmldoc/file.c"}}]}}],"schema_version":"1.7.5","severity":[{"type":"CVSS_V3","score":"CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H"}]}