CRITICAL

CVE-2026-75957

CVSS v3

9.8

CRITICAL

EPSS Score

—

exploit probability

CISA KEV

known exploited

Exploitation

—

SSVC status

Description

The Ultimate Multisite – WordPress Multisite SaaS & WaaS Platform plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 2.15.0 via the `checkout_form` parameter of the `login_customer_after_checkout` function. This is due to the publicly accessible `wu_ajax_nopriv_wu_validate_form` AJAX handler accepting a freely obtainable checkout nonce, and the `checkout_form=wu-finish-checkout` parameter causing `get_validation_rules()` to discard all validation ru

Technical details

CVSS v3 Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Published: 2026-10-01
Last Modified: 2026-10-01

Frequently asked questions

What is CVE-2026-75957?

Is CVE-2026-75957 actively exploited?

Active exploitation of CVE-2026-75957 has not been confirmed.

What is the CVSS score for CVE-2026-75957?

CVE-2026-75957 has a CVSS v3 base score of 9.8 (CRITICAL severity), with vector string CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H.

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