The Ultimate Multisite WordPress plugin before 2.17.0 does not require authentication before a logged-out checkout is linked to, and logged in as, an existing WordPress account matching the submitted email address, and its duplicate-account check normalizes that address differently from the lookup used to create the customer, so an unauthenticated attacker can log in as any existing user, including a Network Super Admin, whose email address they know.
This bypass is not addressed by the 2.15.1 fix for CVE-2026-75957 and remains exploitable in all versions up to and including 2.16.1, the releases that fix was expected to cover. Exploitation requires a checkout form configured without a password field (auto-generated password) and a target account that has no existing customer record in the Ultimate Multisite WordPress plugin before 2.17.0.
References
Configurations
No configuration.
History
08 Oct 2026, 11:16
| Type | Values Removed | Values Added |
|---|---|---|
| CVSS |
v2 : v3 : |
v2 : unknown
v3 : 9.8 |
| CWE | CWE-287 |
08 Oct 2026, 06:16
| Type | Values Removed | Values Added |
|---|---|---|
| New CVE |
Information
Published : 2026-10-08 06:16
Updated : 2026-10-08 20:51
NVD link : CVE-2026-103646
Mitre link : CVE-2026-103646
CVE.ORG link : CVE-2026-103646
JSON object : View
Products Affected
No product.
CWE
CWE-287
Improper Authentication
