User Submitted Posts Plugin up to 20260113 on WordPress POST Request usp_get_submitted_category Category improper authentication

Summaryinfo

A vulnerability was found in User Submitted Posts Plugin up to 20260113 on WordPress. It has been classified as critical. Affected by this issue is the function usp_get_submitted_category of the component POST Request Handler. This manipulation of the argument Category causes improper authentication. This vulnerability is registered as CVE-2026-2126. Remote exploitation of the attack is possible. No exploit is available.

Detailsinfo

A vulnerability was found in User Submitted Posts Plugin up to 20260113 on WordPress. It has been declared as critical. Affected by this vulnerability is the function usp_get_submitted_category of the component POST Request Handler. The manipulation of the argument category with an unknown input leads to a improper authentication vulnerability. The CWE definition for the vulnerability is CWE-287. When an actor claims to have a given identity, the product does not prove or insufficiently proves that the claim is correct. As an impact it is known to affect confidentiality, integrity, and availability. The summary by CVE is:

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.

It is possible to read the advisory at wordfence.com. This vulnerability is known as CVE-2026-2126. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. Technical details of the vulnerability are known, but there is no available exploit. The pricing for an exploit might be around USD $0-$5k at the moment (estimation calculated on 02/18/2026).

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Productinfo

Type

• WordPress Plugin

Name

• User Submitted Posts Plugin

Version

• 20260113

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

CVSSv4info

CVSSv3info

CVSSv2info

Exploitinginfo

Threat Intelligenceinfo

Countermeasuresinfo

Timelineinfo

Sourcesinfo

Entryinfo

Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.

Discussion