cvedb.io
CVE-2026-33347
MEDIUM · CVSS 6.1
EPSS exploitation probability: 0%
Published 2026-03-24T20:16:29.240 · Last modified 2026-06-17T10:37:21.270

Summary

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.

Affected products

thephpleague — commonmark

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References

This product uses data from the NVD API but is not endorsed or certified by the NVD. Informational only; not professional security advice.