What’s Vulnerable › Vulnerabilities

CVE-2026-1987: Scheduler Widget <= 0.1.6 - Insecure Direct Object Reference to Authenticated (Subscriber+) Arbitrary Event Modification

• Severity: medium (CVSS 5.4 v3.1)
• Exploited in the wild: not listed in CISA KEV
• EPSS: 0.4% probability of exploitation in the next 30 days
• Public exploit or detection template: none known
• Published: 2026-02-14 · updated 2026-06-17
• Weakness: CWE-639

Description

The Scheduler Widget plugin for WordPress is vulnerable to Insecure Direct Object Reference in all versions up to, and including, 0.1.6. This is due to the `scheduler_widget_ajax_save_event()` function lacking proper authorization checks and ownership verification when updating events. This makes it possible for authenticated attackers, with Subscriber-level access and above, to modify any event in the scheduler via the `id` parameter granted they have knowledge of the event ID.

Affected products

• morelmathieuj Scheduler Widget: through 0.1.6

References

• https://cwe.mitre.org/data/definitions/639.html
• https://cwe.mitre.org/data/definitions/862.html
• https://owasp.org/www-project-web-security-testing-guide/latest/4-Web_Application_Security_Testing/05-Authorization_Testing/04-Testing_for_Insecure_Direct_Object_References
• https://plugins.trac.wordpress.org/browser/scheduler-widget/tags/0.1.6/scheduler-widget.php#L158
• https://plugins.trac.wordpress.org/browser/scheduler-widget/trunk/scheduler-widget.php#L158
• https://www.wordfence.com/threat-intel/vulnerabilities/id/fd5f370c-743f-41f1-80ab-7f0805cae38c?source=cve

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