WP OAuth Server < 6.4.0 - Subscriber+ Cross-User Account Takeover via OIDC ID Token Substitution (CVE-2026-82843) | HOL Guard CVE

Unknown severity · Source severity not reportedCVE-2026-82843

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

Answer in brief

CVE-2026-82843 records a Unknown severity vulnerability in WP OAuth Server < 6.4.0 - Subscriber+ Cross-User Account Takeover via OIDC ID Token Substitution. The current sources do not mark it as known exploited. The current feed maps Unknown/WP OAuth Server ( Login with WordPress ) (generic). Check affected ranges and fixed versions before updating.

Analysis pending evidence review

HOL Guard separates source facts from reviewed analysis. See the methodology.

Published Sep 23, 2026Updated Sep 23, 2026Source checked Sep 23, 2026First seen by HOL Sep 23, 2026Material review Sep 23, 2026

Upstream Advisory

Key facts

Risk: Unknown severitySource severity not reported
Exploitation: Not marked as known exploited
Affected software: 1 mapped package or product
Fix availability: Available

Why this deserves its current priority

A CVSS score is not reported in the current record. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Unknown/WP OAuth Server ( Login with WordPress ) (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Unknown/WP OAuth Server ( Login with WordPress )generic	>=0 <6.4.0	6.4.0

Recommended response

Check inventory. Check lockfiles and deployed manifests for Unknown/WP OAuth Server ( Login with WordPress ).
Review the reported fix. Update Unknown/WP OAuth Server ( Login with WordPress ) to 6.4.0 if you use the affected versions. Test the change in a non-production environment first.

Evidence timeline and material changes

Published upstream
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Sep 23, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Sep 23, 2026

Sources and claim methodology

Source referencewpscan.com

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.