CVE-2026-8365
Published: Tue, 09 Jun 2026 09:16
Summary
The Blocksy theme for WordPress is vulnerable to PHP Object Injection leading to Remote Code Execution via the 'blocksy_meta' REST API field and the V200 database migration in versions up to and inclu
Details
The Blocksy theme for WordPress is vulnerable to PHP Object Injection leading to Remote Code Execution via the 'blocksy_meta' REST API field and the V200 database migration in versions up to and including 2.1.35. This is due to insufficient input sanitization in the blocksy_sanitize_post_meta_options() function, which only blocks values containing '<' or '>' and does not prevent serialized PHP object strings from being stored in post meta, combined with the SearchReplacer::run_recursively() function unconditionally deserializing all string values via @unserialize() during migration without restricting allowed classes. This makes it possible for authenticated attackers, with contributor-level access and above, to inject a serialized Blocksy\RaiiPattern object into post meta that, when the V200 migration runs on an upgraded site, is deserialized and triggers RaiiPattern::__destruct(), which executes arbitrary PHP callables via call_user_func().
Are YOU affected by CVE-2026-8365?
5-second check on your actual server. Reads /etc/os-release, uname -r, and dpkg-query; matches against the live USN + Debian Security Tracker feeds; tells you whether CVE-2026-8365 (and any other live CVE) applies. Anonymous, no signup.
curl https://mindsparkstack.com/scan.sh | bash
References
- https://themes.trac.wordpress.org/browser/blocksy/2.1.35/admin/helpers/meta-boxes.php#L104
- https://themes.trac.wordpress.org/browser/blocksy/2.1.35/admin/helpers/validator.php#L75
- https://themes.trac.wordpress.org/browser/blocksy/2.1.35/inc/classes/db-versioning/utils/db-search-replacer.php#L98
- https://themes.trac.wordpress.org/browser/blocksy/2.1.35/inc/classes/raii.php#L12
- https://themes.trac.wordpress.org/browser/blocksy/2.1.41/admin/helpers/meta-boxes.php#L104
- https://themes.trac.wordpress.org/browser/blocksy/2.1.41/admin/helpers/validator.php#L75
- https://themes.trac.wordpress.org/browser/blocksy/2.1.41/inc/classes/db-versioning/utils/db-search-replacer.php#L98
- https://themes.trac.wordpress.org/browser/blocksy/2.1.41/inc/classes/raii.php#L12
- https://themes.trac.wordpress.org/browser/blocksy/trunk/admin/helpers/meta-boxes.php#L104
- https://themes.trac.wordpress.org/browser/blocksy/trunk/admin/helpers/validator.php#L75
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