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.

INFO

Published Date :

2026-03-24T19:26:23.872Z

Last Modified :

2026-03-26T19:52:12.754Z

Source :

GitHub_M
AFFECTED PRODUCTS

The following products are affected by CVE-2026-33347 vulnerability.

Vendors Products
Thephpleague
  • Commonmark
REFERENCES

Here, you will find a curated list of external links that provide in-depth information to CVE-2026-33347.

URL Resource
https://github.com/thephpleague/commonmark/commit/59fb075d2101740c337c7216e3f32b36c204218b cve-icon cve-icon
https://github.com/thephpleague/commonmark/releases/tag/2.8.2 cve-icon cve-icon
https://github.com/thephpleague/commonmark/security/advisories/GHSA-hh8v-hgvp-g3f5 cve-icon cve-icon
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CVSS Vulnerability Scoring System

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Detailed values of each vector for above chart.
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User Interaction
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Integrity Impact
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