---
id: "CVE-2026-110018"
kind: "vulnerability"
aliases: ["CVE-2026-110018"]
title: "aBlocks WordPress plugin: Contributor can escalate to Editor role"
severity: "high"
cvss: 8.8
epss: null
exploited: false
status: "open"
category: "package"
products: []
ecosystems: []
tags: ["package", "self-hosted", "wordpress", "wordpress-plugin"]
not_affected_if: ["no-contributor-accounts", "patched-version", "plugin-not-installed"]
published_at: "2026-10-24T12:16:54+00:00"
first_seen_at: "2026-10-24T12:47:58+00:00"
updated_at: "2026-10-25T02:59:57+00:00"
sources: [{"source": "nvd", "url": "https://nvd.nist.gov/vuln/detail/CVE-2026-110018", "first_seen_at": "2026-10-24T12:47:58+00:00"}]
---

# aBlocks WordPress plugin: Contributor can escalate to Editor role

The aBlocks WordPress plugin up to and including 2.17.0 exposes a REST registration endpoint whose handler trusts a roleSlug stored in post block attributes, without checking the form type at request time. A logged-in Contributor can save a crafted block, trigger the endpoint, and receive a session at a higher role, up to Editor.

_Summary, check and fix written by a model from the sources; labelled as such._

## How to check

- Check the installed aBlocks plugin version in the WordPress admin Plugins screen, or with `wp plugin get ablocks --field=version` (the package name is unknown from sources, so confirm the slug)
- Look for the `/ablocks/v1/form-builder/registration` REST route with `curl -s https://example.com/wp-json/ablocks/v1/` and check whether it is listed

## Fix

- Update the aBlocks plugin to a version newer than `2.17.0`; the patched version number is unknown from sources
- Until patched, deactivate the plugin or restrict Contributor accounts, and review user roles for unexpected Editor accounts created after exposure

## Timeline

- 2026-10-24T12:47:58+00:00 nvd https://nvd.nist.gov/vuln/detail/CVE-2026-110018

## From the sources

The aBlocks – Gutenberg Blocks, User Dashboard Builder, Popup Builder, Form Builder & Animation Builder plugin for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 2.17.0 via the `/ablocks/v1/form-builder/registration` REST endpoint. The vulnerability exists because the endpoint is registered with `permission_callback => __return_true` and the `register()` handler reads `roleSlug` directly from attacker-controlled block attributes in `post_content` without ever verifying that the block's `formType` is `registration` — a condition that `RegistrationFormSanitizer::verify()` imposes only at save-time, meaning a Contributor can preserve an arbitrary `roleSlug` by saving a block with `formType='login'` and then triggering the endpoint via a valid `wp_rest` nonce and post-ownership check. This makes it possible for authenticated attackers, with Contributor-level access and above, to escalate their WordPress role to Editor or any other non-administrator role and receive a fully authenticated session at the elevated privilege level via `WP_User::set_role()` and `wp_set_auth_cookie()`. Escalation is bounded below administrator-tier roles because `is_safe_registration_role()` rejects any role holding `manage_options`, `edit_users`, `delete_users`, `create_users`, `promote_users`, or `edit_theme_options`, meaning the highest practically reachable role on a standard WordPress installation is Editor.

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