Kirki public form route permits arbitrary shortcode execution
Kirki before 6.2.1 exposes POST /wp-json/kirki/v1/frontend/form to unauthenticated visitors. A request can supply unsigned _kirki_form metadata and form fields; the submission service loads the selected form configuration and EmailActionHandler::send_single_email_action() passes configured recipient, Reply-To, name and subject fields through do_shortcode() before wp_mail(). This allows any shortcode registered on the site to run. On a default installation, the CNA says this can disclose the administrator email address and relay mail to an attacker-chosen recipient. Version 6.2.1 signs the metadata and restricts shortcode replacement to approved placeholders. The exact reporter payload is not disclosed.
- Component
- Kirki
- Plugin slug
kirki- Affected
- < 6.2.1
- Safe version
6.2.1- Published
- Aug 12, 2026
This CVE was published Aug 12, 2026 and is one of 42 known issues for this plugin.
Update, patch or deactivate.
Update to 6.2.1 or later. Review public Kirki form submissions and outbound mail, and inspect installed shortcodes for sensitive actions that may have been exposed through the route.
A safe version is available, so updating to that version or later is the preferred remediation. If an immediate update is not practical, consider a targeted application patch or temporarily restricting the affected functionality.
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 WordPress plugin before 6.2.1 does not properly authorise its front-end form submission REST routes and passes attacker-controlled input through shortcode execution, allowing unauthenticated users to run any shortcode registered on the site, which on a default install leads to disclosure of the site administrator's email address and an arbitrary-recipient mail relay from the victim's domain.
CVE / CNA vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:N