Kirki – Freeform Page Builder, Website Builder & Customizer: PHP object injection
The Kirki – Freeform Page Builder, Website Builder & Customizer plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 6.3.2 via deserialization of untrusted input . This makes it possible for authenticated attackers, with administrator-level access and above, to inject a PHP Object. No known POP chain is present in the vulnerable software, which means this vulnerability has no impact unless another plugin or theme containing a POP chain is installed on the site. If a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to perform actions like delete arbitrary files, retrieve sensitive data, or execute code depending on the POP chain present. By default, Editor-level users are granted FULL_ACCESS to the plugin's import endpoint via the KIRKI_USERS_DEFAULT_FULL_ACCESS configuration, meaning exploitation is possible at Editor privilege level rather than being restricted to administrators alone. The export initially names Administrator access but explicitly identifies Editor access under the default FULL_ACCESS configuration. Do not assume this is restricted to administrators; a suitable object chain in another installed component is still required for the stated downstream impacts. The export supplies no additional endpoint, action, parameter or function details beyond those described above.
- Component
- Kirki – Freeform Page Builder, Website Builder & Customizer
- Plugin slug
kirki- Affected
- <= 6.3.2
- Safe version
- See mitigation notes
- Published
- Oct 17, 2026
This CVE was published Oct 17, 2026 and is one of 42 known issues for this plugin.
Update, patch or deactivate.
Official author notes reviewed on 2026-10-17 through 6.4.0 did not establish a fixed version for this CVE. No matching import deserialization restriction; role-manager changes within affected 6.3.2 do not establish remediation. This archive's uncertainty does not establish that the current release remains vulnerable. Consult the author for current remediation guidance; restrict or disable affected functionality when warranted. Official notes: https://wordpress.org/plugins/kirki/#developers. Restrict import access to trusted administrators where warranted and avoid deserializing imported data into unrestricted PHP objects.
No confirmed safe version is listed. Consider a vendor-supported patch or temporarily restricting the affected functionality while you assess the risk.
Deactivate only when warranted by your risk profile, or when advised by your hosting provider in the limited circumstances where the vulnerability cannot otherwise be mitigated. If you’re unsure which action is appropriate, contact Fused or your hosting provider for guidance.
Technical description
The Kirki – Freeform Page Builder, Website Builder & Customizer plugin for WordPress is vulnerable to PHP Object Injection in all versions up to, and including, 6.3.2 via deserialization of untrusted input . This makes it possible for authenticated attackers, with administrator-level access and above, to inject a PHP Object. No known POP chain is present in the vulnerable software, which means this vulnerability has no impact unless another plugin or theme containing a POP chain is installed on the site. If a POP chain is present via an additional plugin or theme installed on the target system, it may allow the attacker to perform actions like delete arbitrary files, retrieve sensitive data, or execute code depending on the POP chain present. By default, Editor-level users are granted FULL_ACCESS to the plugin's import endpoint via the KIRKI_USERS_DEFAULT_FULL_ACCESS configuration, meaning exploitation is possible at Editor privilege level rather than being restricted to administrators alone.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:H/UI:N/S:U/C:H/I:H/A:H
Primary and upstream sources
- NVD record for CVE-2026-104734
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- WordPress upstream reference plugins.trac.wordpress.org
- Wordfence advisory wordfence.com