CVE-2026-5388 – justhtml before 1.15.0 Multiple Security Issues

​CVE ID :CVE-2026-5388

Published : Aug. 23, 2026, 2:16 p.m. | 4 hours, 29 minutes ago

Description :justhtml before 1.15.0 contains multiple security issues in URL sanitization helpers (clean_url_value/clean_url_in_js_string), HTML serialization, Markdown passthrough (html_passthrough=True), and several custom sanitization-policy edge cases. Depending on configuration, an attacker can bypass sanitization to inject active HTML and JavaScript — for example via encoded javascript: URLs, backslash-based relative URLs resolved as remote hosts, markup-breaking programmatic element/attribute names or HTML comments, raw reintroduction through Markdown passthrough, or preserved To Read More Visit Read More