Stylemixmes Masterstudy Plugin up to 4.8.151 on WordPress AJAX Action masterstudy_ms_stm_set_discard_transient stm_developer_access_token privileges management

Summaryinfo

A vulnerability was found in Stylemixmes Masterstudy Plugin up to 4.8.151 and classified as critical. Affected is the function masterstudy_ms_stm_set_discard_transient of the component AJAX Action. The manipulation of the argument stm_developer_access_token results in privileges management. This vulnerability is cataloged as CVE-2026-13764. The attack may be launched remotely. There is no exploit available.

Detailsinfo

A vulnerability, which was classified as critical, was found in Stylemixmes Masterstudy Plugin up to 4.8.151. Affected is the function masterstudy_ms_stm_set_discard_transient of the component AJAX Action. The manipulation of the argument stm_developer_access_token with an unknown input leads to a privileges management vulnerability. CWE is classifying the issue as CWE-269. The product does not properly assign, modify, track, or check privileges for an actor, creating an unintended sphere of control for that actor. This is going to have an impact on confidentiality, integrity, and availability. CVE summarizes:

The Masterstudy - Education WordPress Theme theme for WordPress is vulnerable to Privilege Escalation in all versions up to, and including, 4.8.151. This is due to missing authorization and nonce validation on the `masterstudy_ms_stm_set_discard_transient` AJAX action. This makes it possible for authenticated attackers, with Subscriber-level access and above, to elevate their privileges to Administrator by setting the `stm_developer_access_token` transient and using the developer access auto-login flow to obtain administrator session cookies.

The advisory is available at wordfence.com. This vulnerability is traded as CVE-2026-13764 since 06/29/2026. The exploitability is told to be easy. It is possible to launch the attack remotely. Technical details are known, but there is no available exploit. The structure of the vulnerability defines a possible price range of USD $0-$5k at the moment (estimation calculated on 11/12/2026). This vulnerability is assigned to T1068 by the MITRE ATT&CK project.

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

If you want to get best quality of vulnerability data, you may have to visit VulDB.

Productinfo

Type

• WordPress Plugin

Vendor

• Stylemixmes

Name

• Masterstudy Plugin

Version

• 4.8.151

CPE 2.3info

• 🔒

CPE 2.2info

• 🔒

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Entryinfo

If you want to get best quality of vulnerability data, you may have to visit VulDB.

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