# CVE-2026-57317: NSquared Simply Schedule Appointments unauthenticated XSS

Source: https://junglewise.ai/threats/cve-2026-57317-nsquared-simply-schedule-appointments-unauthenticated-xss  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-06-26. Updated: 2026-06-26  
License: CC BY 4.0 with a link back

CVE-2026-57317 · Severity: high · CVSS 7.1 · Published 2026-06-26

Simply Schedule Appointments, a popular WordPress plugin used for managing bookings and client meetings, contains a security flaw that allows attackers to inject malicious scripts into the website. Because this vulnerability can be exploited without logging in, an attacker could trick a site administrator or visitor into clicking a link that executes code in their browser. This could lead to unauthorized actions being performed on behalf of the user, such as redirecting visitors to malicious sites or stealing sensitive session information.

## Quick answers

**Is CVE-2026-57317 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-57317 being exploited in the wild.

**How severe is CVE-2026-57317?** High severity, with a CVSS score of 7.1, published 26 June 2026.

**Which products and versions are affected?** NSquared Simply Schedule Appointments <= 1.6.12.2.

**Is there a fix for CVE-2026-57317?** A patch was published on 2026-06-26: Patch available in version 1.6.12.4 Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-57317 attacked?** It is attacked over the network, in a network appliance.

**Am I affected by CVE-2026-57317?** Check whether anything you run is named in the advisory. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## Technical details

A Reflected Cross-Site Scripting (XSS) vulnerability exists in the NSquared Simply Schedule Appointments plugin for WordPress (versions <= 1.6.12.2). The flaw stems from improper neutralization of user-supplied input during web page generation (CWE-79). An unauthenticated remote attacker can exploit this by crafting a malicious URL and tricking a victim (typically an administrator or authenticated user) into visiting it. Successful exploitation allows the execution of arbitrary JavaScript in the context of the victim's browser session, potentially leading to session hijacking or unauthorized administrative actions. The issue is resolved in version 1.6.12.4.

## Affected products

- NSquared Simply Schedule Appointments <= 1.6.12.2

## Timeline

- 2026-06-06: disclosed: Reported by vnth4nhnt
- 2026-06-26: advisory: Published by Patchstack and NVD
- 2026-06-26: patched: Patch available in version 1.6.12.4

## References

- [https://wordpress.org/plugins](https://wordpress.org/plugins)
- [https://patchstack.com/database/wordpress/plugin/simply-schedule-appointments/vulnerability/wordpress-simply-schedule-appointments-plugin-1-6-12-2-cross-site-scripting-xss-vulnerability?_s_id=cve](https://patchstack.com/database/wordpress/plugin/simply-schedule-appointments/vulnerability/wordpress-simply-schedule-appointments-plugin-1-6-12-2-cross-site-scripting-xss-vulnerability?_s_id=cve)