- Critical 9.0
CVE-2026-82843
The WP OAuth Server ( Login with WordPress ) WordPress plugin before 6.4.0 does not bind the OpenID Connect identity assertion it issues to the authorization grant being exchanged, returning instead the assertion belonging to whichever user authenticated most recently, which allows users with the Subscriber role and above to obtain a validly signed identity assertion for another user, including an administrator, and authenticate as them at any application that uses the site for single sign-on.
Scores
The facts
- Published
- 23 September 2026
- Last changed
- 24 September 2026
- NVD status
- Deferred
- Severity
- Critical, CVSS 9.0 out of 10 (version 3.1)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:H - Weakness
- Known exploited
- Not in the CISA Known Exploited Vulnerabilities catalogue in this build.
- EPSS
- 0.2% chance of exploitation activity in the next 30 days (percentile 8).
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