UBUNTU-CVE-2026-33347

league/commonmark is a PHP Markdown parser. From version 2.3.0 to before version 2.8.2, the DomainFilteringAdapter in the Embed extension is vulnerable to an allowlist bypass due to a missing hostname boundary assertion in the domain-matching regex. An attacker-controlled domain like...

CVE-2026-33347

Summary: CVE-2026-33347 affects league/commonmark’s Embed extension DomainFilteringAdapter. A missing hostname boundary assertion in the domain-matching regex allows an attacker-controlled domain (e.g., youtube.com.evil) to bypass the allowlist, potentially treating untrusted content as allowed. ...