Blocksy <= 2.1.41 - Authenticated (Contributor+) PHP Object Injection via Deserialization of Untrusted Data via 'blocksy_meta' REST API Field_CVE-2026-8365

{
    "lastseen": "",
    "description": "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().",
    "published": "2026-06-09T08:29:40.638Z",
    "modified": "2026-06-09T08:29:40.638Z",
    "type": "cve",
    "title": "Blocksy <= 2.1.41 - Authenticated (Contributor+) PHP Object Injection via Deserialization of Untrusted Data via 'blocksy_meta' REST API Field",
    "source": "Wordfence",
    "references": "https://www.wordfence.com/threat-intel/vulnerabilities/id/fd216743-ce8d-4632-9fd1-d63502c2dfcd?source=cve\nhttps://themes.trac.wordpress.org/browser/blocksy/trunk/inc/classes/db-versioning/utils/db-search-replacer.php#L98\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.41/inc/classes/db-versioning/utils/db-search-replacer.php#L98\nhttps://themes.trac.wordpress.org/browser/blocksy/trunk/admin/helpers/meta-boxes.php#L104\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.41/admin/helpers/meta-boxes.php#L104\nhttps://themes.trac.wordpress.org/browser/blocksy/trunk/admin/helpers/validator.php#L75\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.41/admin/helpers/validator.php#L75\nhttps://themes.trac.wordpress.org/browser/blocksy/trunk/inc/classes/raii.php#L12\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.41/inc/classes/raii.php#L12\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.35/inc/classes/db-versioning/utils/db-search-replacer.php#L98\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.35/admin/helpers/meta-boxes.php#L104\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.35/admin/helpers/validator.php#L75\nhttps://themes.trac.wordpress.org/browser/blocksy/2.1.35/inc/classes/raii.php#L12",
    "id": "CVE-2026-8365",
    "bulletinFamily": "",
    "cwe": [
        "CWE-502"
    ],
    "cvelist": null,
    "sourceData": "creativethemeshq Blocksy 0",
    "sourceHref": "",
    "cvss": {
        "score": 8.8,
        "severity": "HIGH",
        "vector": "CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H",
        "version": "3.1"
    },
    "cvss2": [],
    "cvss3": {
        "version": "",
        "vectorString": "",
        "baseScore": 0,
        "baseSeverity": "",
        "attackVector": "",
        "attackComplexity": "",
        "privilegesRequired": "",
        "userInteraction": "",
        "scope": "",
        "confidentialityImpact": "",
        "integrityImpact": "",
        "availabilityImpact": "",
        "cvssV3": {
            "version": "",
            "vectorString": "",
            "baseScore": 0,
            "baseSeverity": "",
            "attackVector": "",
            "attackComplexity": "",
            "privilegesRequired": "",
            "userInteraction": "",
            "scope": "",
            "confidentialityImpact": "",
            "integrityImpact": "",
            "availabilityImpact": ""
        }
    },
    "href": "",
    "category_name": "CVE",
    "post_link": "",
    "product": "Blocksy",
    "version": "0",
    "vendor": "creativethemeshq",
    "ai_description": "PHP Object Injection vulnerability in Blocksy theme for WordPress, allowing remote code execution via the 'blocksy_meta' REST API field and V200 database migration in versions up to and including 2.1.35.",
    "ai_severity": "High",
    "ai_vendor": "Creative Themes HQ",
    "ai_product": "Blocksy",
    "ai_version": "2.1.35 and prior",
    "ai_score": 8.8
}