CVE-2026-13764: Auth Bypass (CVSS 8.8)

Description

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.

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CVSS v3.1 Score

8.8

HIGH

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Weakness Type (CWE)

CWE-862 Missing Authorization

References

Other References

https://docs.stylemixthemes.com/masterstudy-theme-documentation/extra-materials/changelog https://themeforest.net/item/masterstudy-education-center-wordpress-theme/12170274 https://www.wordfence.com/threat-intel/vulnerabilities/id/ec898f73-d275-4624-911b-89d9a945ff92?source=cve

Frequently Asked Questions

What is CVE-2026-13764? +

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. It has a CVSS v3.1 base score of 8.8 (HIGH).

How severe is CVE-2026-13764? +

CVE-2026-13764 has a CVSS v3.1 score of 8.8 out of 10, rated HIGH. This is a high-severity vulnerability that should be prioritized for patching.

How do I check if I'm vulnerable to CVE-2026-13764? +

You can use Secably's free Website Scanner to check your website for known vulnerabilities. For infrastructure scanning, use the Port Scanner to identify exposed services that may be affected. Check the vendor advisories linked above for specific patch and version information.

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