CVE-2026-22351
Published: 20 February 2026
Summary
CVE-2026-22351 is a high-severity Missing Authorization (CWE-862) vulnerability. Its CVSS base score is 7.5 (High).
Operationally, exploitation aligns with the MITRE ATT&CK technique Exploit Public-Facing Application (T1190); ranked at the 15.1th percentile by exploit likelihood (below the median); it is not currently listed in the CISA KEV catalog.
The strongest mitigations our analysis identified are NIST 800-53 AC-3 (Access Enforcement) and SI-2 (Flaw Remediation).
Deeper analysis
CVE-2026-22351 is a missing authorization vulnerability (CWE-862) in the WP FullCalendar WordPress plugin, developed by Marcus (aka @msykes) and known as wp-fullcalendar. The flaw enables exploitation of incorrectly configured access control security levels and affects all versions from n/a through 1.6 inclusive. It carries a CVSS v3.1 base score of 7.5 (AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N), reflecting high severity due to network accessibility and significant confidentiality impact.
Unauthenticated attackers (PR:N) can exploit this vulnerability over the network (AV:N) with low attack complexity (AC:L) and no user interaction (UI:N). Successful exploitation allows unauthorized access to sensitive data, resulting in high confidentiality impact (C:H) without affecting integrity or availability.
The Patchstack advisory (https://patchstack.com/database/Wordpress/Plugin/wp-fullcalendar/vulnerability/wordpress-wp-fullcalendar-plugin-1-6-broken-access-control-vulnerability?_s_id=cve) documents this broken access control issue in WP FullCalendar version 1.6, providing details relevant to mitigation for affected WordPress installations.
EU & UK References
- 🇪🇺 ENISA EUVD: EUVD-2026-7490
Vulnerability details
Missing Authorization vulnerability in Marcus (aka @msykes) WP FullCalendar wp-fullcalendar allows Exploiting Incorrectly Configured Access Control Security Levels.This issue affects WP FullCalendar: from n/a through <= 1.6.
- CWE(s)
Related Threats
MITRE ATT&CK Enterprise TechniquesAI
Why these techniques?
Missing authorization (CWE-862) in a public-facing WordPress plugin directly enables unauthenticated network exploitation for sensitive data access, matching T1190.
CVEs Like This One
Affected Assets
Mitigating Controls
Mitigating Controls (NIST 800-53 r5) AI
Directly mitigates the missing authorization vulnerability by requiring timely identification, reporting, and correction of the flaw in the WP FullCalendar plugin.
Enforces approved authorizations to block unauthenticated attackers from accessing sensitive data through the broken access control in the vulnerable plugin.
Limits the impact of unauthorized access by ensuring only least privilege is granted, reducing the scope of sensitive data exposure in the exploited plugin.