CVE-2026-2991
CWE-287Published: March 18, 2026· Updated: Mar 19, 2026
Official Description
The KiviCare – Clinic & Patient Management System (EHR) plugin for WordPress is vulnerable to Authentication Bypass in all versions up to, and including, 4.1.2. This is due to the `patientSocialLogin()` function not verifying the social provider access token before authenticating a user. This makes it possible for unauthenticated attackers to log in as any patient registered on the system by providing only their email address and an arbitrary value for the access token, bypassing all credential verification. The attacker gains access to sensitive medical records, appointments, prescriptions, and billing information (PII/PHI breach). Additionally, authentication cookies are set before the role check, meaning the auth cookies for non-patient users (including administrators) are also set in the HTTP response headers, even though a 403 response is returned.
Technical Analysis
CVE-2026-2991 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
From a weakness classification perspective (CWE-287): Authentication bypass vulnerabilities allow attackers to access protected resources without valid credentials.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
All References (4)
Quick Facts
Related CVEs (CWE-287)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2026-2991 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts