CVE-2026-82843

WP OAuth Server < 6.4.0 - Subscriber+ Cross-User Account Takeover via OIDC ID Token Substitution

State
Published
Severity
9.0 Critical
Published
Sep 23, 2026
Updated
Sep 23, 2026
Reserved
Aug 31, 2026

Read the record on cve.org

Description

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

CVSSScoreVectorSource
3.19.0 CriticalCVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:H/I:H/A:HCISA-ADP

Weaknesses

Affected Products

ProductVersions
WP OAuth Server ( Login with WordPress )Unknown
  • before 6.4.0Affected

References

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