Medium severity · published May 27, 2026
CVE-2026-7493
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin <= 1.6.11.5 - Unauthenticated Denial of Service
5.3
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L
Attack vector
Network
Complexity
Low
Privileges
None
User interaction
None
Confidentiality
None
Integrity
None
Availability
Low
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 28% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
AB
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin · croixhaug
through 1.6.11.5 · source: vendor
Affected product
AB
Appointment Booking Calendar — Simply Schedule Appointments Booking Plugin
croixhaug
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-7493
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-7493
plugins.trac.wordpress.org
https://plugins.trac.wordpress.org/browser/simply-schedule-appointments/tags/1.6.11.2/includes/class-async-action-model.php#L173
www.wordfence.com
https://www.wordfence.com/threat-intel/vulnerabilities/id/ae66228e-d086-44fd-8acb-5a99482cedfb?source=cve
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