Vulnerability · Published May 27, 2026 · Assigned by Wordfence

CVE-2026-7493Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.11.5 - Unauthenticated Denial of Service

Medium 5.3

In plain English

A medium-severity uncontrolled resource consumption in Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin from croixhaug. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.4% (higher than 29% of all known vulnerabilities).

Severity (CVSS 3.1)5.3Medium

Exploit odds (30 days)0.4%top 71.2% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

The Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin plugin for WordPress is vulnerable to denial of service in all versions up to, and including, 1.6.11.5. This is due to a publicly accessible REST API endpoint (/wp-json/ssa/v1/async) that calls PHP's sleep() function on a user-supplied delay parameter without any rate limiting. This makes it possible for unauthenticated attackers to exhaust PHP worker processes, denying access to the site to legitimate users.

Affected products (as reported)

Vendor	Product	Versions
croixhaug	Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin	0 – through 1.6.11.5

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L

In plain English

Official description

Affected products (as reported)

References