CVE-2026-111727
Appointment Booking Calendar <= 1.4.05 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'vs_text_submitbtn' Parameter
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'vs_text_submitbtn' parameter in all versions up to, and including, 1.4.05 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to be assigned as a calendar owner, a per-user grant that any administrator can extend to users as low as Subscriber level through the plugin's calendar list screen. Exploitation by attackers with subscriber-level access and above requires that an administrator has assigned the attacker's account as owner (conwer) of a calendar via the plugin's calendar list screen; the plugin's UI lists all registered users regardless of role, so a Subscriber can be assigned. On a default installation, where that is not configured, the vulnerability requires attackers with editor-level access and above.
Attack profile
How easy it is to exploit
- Attack vector
- Network
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- None
What an attacker can affect
- Confidentiality
- Low
- Integrity
- Low
- Availability
- None
Exploit likelihood
What each source reports
CVE List Score used
6.4
Appointment Booking Calendar <= 1.4.05 - Authenticated (Subscriber+) Stored Cross-Site Scripting via 'vs_text_submitbtn' Parameter
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'vs_text_submitbtn' parameter in all versions up to, and including, 1.4.05 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to be assigned as a calendar owner, a per-user grant that any administrator can extend to users as low as Subscriber level through the plugin's calendar list screen. Exploitation by attackers with subscriber-level access and above requires that an administrator has assigned the attacker's account as owner (conwer) of a calendar via the plugin's calendar list screen; the plugin's UI lists all registered users regardless of role, so a Subscriber can be assigned. On a default installation, where that is not configured, the vulnerability requires attackers with editor-level access and above.
- Record
CVE-2026-111727- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
EUVDEUVD-2026-111577
6.4
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'vs_text_submitbtn' parameter in all versions up to, and including, 1.4.05 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to be assigned as a calendar owner, a per-user grant that any administrator can extend to users as low as Subscriber level through the plugin's calendar list screen. Exploitation by attackers with subscriber-level access and above requires that an administrator has assigned the attacker's account as owner (conwer) of a calendar via the plugin's calendar list screen; the plugin's UI lists all registered users regardless of role, so a Subscriber can be assigned. On a default installation, where that is not configured, the vulnerability requires attackers with editor-level access and above.
- Record
EUVD-2026-111577- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-fpgw-376p-gw9c
6.4
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site...
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'vs_text_submitbtn' parameter in all versions up to, and including, 1.4.05 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to be assigned as a calendar owner, a per-user grant that any administrator can extend to users as low as Subscriber level through the plugin's calendar list screen. Exploitation by attackers with subscriber-level access and above requires that an administrator has assigned the attacker's account as owner (conwer) of a calendar via the plugin's calendar list screen; the plugin's UI lists all registered users regardless of role, so a Subscriber can be assigned. On a default installation, where that is not configured, the vulnerability requires attackers with editor-level access and above.
- Record
GHSA-fpgw-376p-gw9c- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
NVD
6.4
The Appointment Booking Calendar plugin for WordPress is vulnerable to Stored Cross-Site Scripting via the 'vs_text_submitbtn' parameter in all versions up to, and including, 1.4.05 due to insufficient input sanitization and output escaping. This makes it possible for authenticated attackers, with subscriber-level access and above, to inject arbitrary web scripts in pages that will execute whenever a user accesses an injected page. This requires the attacker to be assigned as a calendar owner, a per-user grant that any administrator can extend to users as low as Subscriber level through the plugin's calendar list screen. Exploitation by attackers with subscriber-level access and above requires that an administrator has assigned the attacker's account as owner (conwer) of a calendar via the plugin's calendar list screen; the plugin's UI lists all registered users regardless of role, so a Subscriber can be assigned. On a default installation, where that is not configured, the vulnerability requires attackers with editor-level access and above.
- Record
CVE-2026-111727- CVSS 3.1
- 6.4 Medium
CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:L/I:L/A:N - Weakness
- CWE-79
- Updated
- 2026-11-02
Affected products
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-111727 is a medium vulnerability (CVSS 6.4) in Codepeople Appointment Booking Calendar, published October 28, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.21%, the 10th percentile. No source names a fixed version.
References
wordfence.com/threat-intel/vulnerabilities/id/dd0e4753-222a-421f-a830-58f6af055dd8?source=cve
plugins.trac.wordpress.org/browser/appointment-booking-calendar/tags/1.4.05/inc/cpabc_scheduler.inc.php
plugins.trac.wordpress.org/browser/appointment-booking-calendar/tags/1.4.05/inc/cpabc_apps_go.inc.php
plugins.trac.wordpress.org/browser/appointment-booking-calendar/tags/1.4.05/inc/cpabc_apps_on.inc.php
plugins.trac.wordpress.org/log/appointment-booking-calendar
plugins.trac.wordpress.org/changeset/3750835/appointment-booking-calendar/trunk/inc/cpabc_scheduler.inc.php
nvd.nist.gov/vuln/detail/CVE-2026-111727
github.com/advisories/GHSA-fpgw-376p-gw9c