{"id":"CVE-2026-8445","title":"justhtml versions <= 1.11.0 (fixed in 1.12.0) do not sufficiently escape HTML-significant characters (angle brackets) in text nodes when converting a parsed document to Markdown via to_markdown()","summary":"justhtml versions <= 1.11.0 (fixed in 1.12.0) do not sufficiently escape HTML-significant characters (angle brackets) in text nodes when converting a parsed document to Markdown via to_markdown(). While a small set of Markdown metacharac…","severity":"critical","cvss":9.8,"cvssVector":"CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H","cwe":["CWE-79"],"vendor":"justhtml","product":"justhtml","affected":["justhtml < 1.12.0"],"patched":["justhtml 1.12.0"],"published":"2026-08-23","updated":"2026-10-12","sourceUpdated":"2026-10-12T16:10:00.220","source":"NVD","sourceUrl":"https://nvd.nist.gov/vuln/detail/CVE-2026-8445","references":[{"url":"https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-3rcm-vjrc-p45j","label":"disclosure@vulncheck.com"},{"url":"https://www.vulncheck.com/advisories/justhtml-before-sanitizer-bypass-via-markdown","label":"disclosure@vulncheck.com"},{"url":"https://github.com/EmilStenstrom/justhtml/security/advisories/GHSA-3rcm-vjrc-p45j","label":"134c704f-9b21-4f2e-91b3-4a467353bcc0"},{"url":"https://github.com/EmilStenstrom/justhtml"}],"tags":["nvd","osv","pip"],"epss":0.00635,"epssPercentile":0.50221,"aliases":["GHSA-3rcm-vjrc-p45j"],"ecosystem":"pip","ingestedAt":"2026-08-24T19:25:43.962Z","slug":"CVE-2026-8445","body":"## Overview\n\njusthtml versions <= 1.11.0 (fixed in 1.12.0) do not sufficiently escape HTML-significant characters (angle brackets) in text nodes when converting a parsed document to Markdown via to_markdown(). While a small set of Markdown metacharacters are escaped, characters such as < and > are preserved, so untrusted input that is safe in to_html() — including entity-decoded text (e.g. &lt;script&gt;) or text from RCDATA/RAWTEXT-parsed elements like <title>, <textarea>, <noscript>, and <plaintext> — can be emitted as raw HTML in the Markdown output, enabling a sanitizer bypass and potential cross-site scripting when that output is rendered.\n\n## Remediation\n\nRefer to the linked advisories for vendor-supplied fixes and affected version ranges.\n\n## Package advisory (CVE-2026-8445)\n\nAffected packages:\n\n- `justhtml < 1.12.0`\n\nPatched in:\n\n- `justhtml 1.12.0`\n\nSource: https://osv.dev/vulnerability/GHSA-3rcm-vjrc-p45j","depth":"midnight","depthScore":54,"depthScoreParts":{"impact":53.9,"likelihood":0.1,"exploitation":0,"ransomware":0},"changes":[{"seq":219491,"id":"CVE-2026-8445","ts":1791824361773,"field":"cvss","old":null,"new":"9.8"},{"seq":219490,"id":"CVE-2026-8445","ts":1791824361773,"field":"severity","old":"medium","new":"critical"}]}