{"cve":"CVE-2026-9769","nvd":{"published":"2026-08-23T14:16:55.277","modified":"2026-10-12T16:10:00.220","status":"Deferred","description":"justhtml through 1.9.1 (fixed in 1.10.0) is vulnerable to uncontrolled recursion leading to denial of service. During JustHTML() construction, TreeBuilder.finish() unconditionally calls _populate_selectedcontent(), which recursively traverses the DOM tree via _find_elements()/_find_element() without a depth bound. An attacker who can supply HTML for parsing can provide deeply nested elements (e.g., ~1000 nested <div> tags, roughly 11 KB) to exceed CPython's default recursion limit and trigger an unhandled RecursionError, which may abort parsing, fail requests, or terminate a worker/process depending on the host application's exception handling.","cvss_v4":{"vector":"CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:H/SC:N/SI:N/SA:N","score":8.7},"cvss_v3":{"version":"3.1","vector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H","score":7.5},"cwes":["CWE-674"],"references":["https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-v7cf-c9rm-wm3j","https://www.vulncheck.com/advisories/justhtml-before-denial-of-service-via-deeply-nested-html","https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-v7cf-c9rm-wm3j"],"products":[],"source":"nvd","synced_at":"2026-10-19T22:49:38.260478770+00:00"},"epss":{"cve":"CVE-2026-9769","score":0.00337,"percentile":0.26814,"date":"2026-10-25"},"kev":null,"osv":[{"id":"GHSA-v7cf-c9rm-wm3j","url":"https://osv.dev/vulnerability/GHSA-v7cf-c9rm-wm3j","summary":"Uncontrolled recursion DoS in JustHTML() via deeply nested HTML","modified":"2026-09-10T12:25:56.970044726Z","packages":[{"ecosystem":"PyPI","name":"justhtml","purl":"pkg:pypi/justhtml","ranges":["<1.10.0"],"fixed":["1.10.0"]}]},{"id":"PYSEC-2026-3854","url":"https://osv.dev/vulnerability/PYSEC-2026-3854","summary":"Uncontrolled recursion DoS in JustHTML() via deeply nested HTML","modified":"2026-09-10T12:15:07.010761627Z","packages":[{"ecosystem":"PyPI","name":"justhtml","purl":"pkg:pypi/justhtml","ranges":["<1.10.0"],"fixed":["1.10.0"]}]}],"attribution":["This product uses the NVD API but is not endorsed or certified by the NVD.","EPSS scores: FIRST Exploit Prediction Scoring System, https://www.first.org/epss","Known exploited vulnerabilities: CISA Known Exploited Vulnerabilities Catalog, https://www.cisa.gov/known-exploited-vulnerabilities-catalog","Package advisories: OSV (https://osv.dev), from the GitHub Advisory Database, PyPA, Go, RustSec and other ecosystem databases, under CC-BY 4.0 or CC0","CVE records: the CVE Program's CVE List (https://www.cve.org), under its terms of use (https://www.cve.org/Legal/TermsOfUse). CVE is a registered trademark of The MITRE Corporation; this product is not affiliated with the CVE Program."]}