CVE-2026-33347
Publication date 24 March 2026
Last updated 23 April 2026
Ubuntu priority
Description
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 youtube.com.evil passes the allowlist check when youtube.com is an allowed domain. This issue has been patched in version 2.8.2.
Status
| Package | Ubuntu Release | Status |
|---|---|---|
| php-league-commonmark | 25.10 questing |
Vulnerable
|
| 24.04 LTS noble |
Fixed 2.4.2-2ubuntu0.1~esm1
|
|
| 22.04 LTS jammy |
Fixed 1.6.7-1ubuntu0.1~esm1
|
|
| 20.04 LTS focal |
Fixed 1.3.1-1ubuntu2+esm1
|
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