CVE-2026-2126

User Submitted Posts <= 20260113 - Incorrect Authorization to Unauthenticated Category Restriction Bypass via 'user-submitted-category' Parameter

2026-02-17 20:36
type5afe

Strategic Overview

Status
Patched in 20260217
Affected Version
<= 20260113
CVSS
5.3Medium
Weakness type
CWE-863 · Incorrect Authorization
CVE
CVE-2026-2126
View all User Submitted Posts – Enable Users to Submit Posts from the Front End vulnerabilities

At a glance

CVE-2026-2126 is a medium-severity Incorrect Authorization vulnerability in the User Submitted Posts WordPress plugin, affecting versions <= 20260113. It carries a CVSS score of 5.3 (reachable over the network; low attack complexity). Exploitation requires no authentication. The issue is fixed in version 20260217; sites on affected versions should update now. Disclosed February 2026, reported by type5afe.

Vulnerability Overview

The User Submitted Posts – Enable Users to Submit Posts from the Front End plugin for WordPress is vulnerable to Incorrect Authorization in all versions up to, and including, 20260113. This is due to the `usp_get_submitted_category()` function accepting user-submitted category IDs from the POST body without validating them against the admin-configured allowed categories stored in `usp_options['categories']`. This makes it possible for unauthenticated attackers to assign submitted posts to arbitrary categories, including restricted ones, by crafting a direct POST request with manipulated `user-submitted-category[]` values, bypassing the frontend category restrictions.

Technical Analysis

The vector marks this flaw as remotely reachable over the network, with low attack complexity — no special timing or configuration is needed, and no privileges on the target site, and no interaction from a victim user.

CWE-863: Incorrect Authorization

User Submitted Posts <= 20260113 carries this weakness at categories, and reaching it takes no account at all. Incorrect authorization means a permission check exists but evaluates the wrong thing, so it passes for callers it was meant to stop.

The action runs for users the code intended to exclude, with the same effect as having no check at all. For User Submitted Posts the fix is 20260217: builds <= 20260113 are affected, anything from 20260217 onward is not.

Remediation

Update to version 20260217, or a newer patched version

How does WordSec protect against this?

This one needs no account at all, which puts it outside what login hardening can reach; WordSec's login security narrows the account-level paths around it, and the firewall is what inspects the request itself. None of that substitutes for the fix: User Submitted Posts 20260217 closes this, and updating the plugin is the step that ends it.

  • Login Security
  • Alerts

External References

Related records

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