CVE-2023-50860: 
WordPress vulnerability analysis and mitigation

A Stored Cross-Site Scripting (XSS) vulnerability was discovered in TMS Booking for Appointments and Events Calendar – Amelia plugin for WordPress, identified as CVE-2023-50860. The vulnerability affects versions up to and including 1.0.85. The issue was initially reported by Ngô Thiên An (ancorn_ from VNPT-VCI) on September 20, 2023, and was publicly disclosed on December 22, 2023 (Patchstack).

The vulnerability stems from improper validation and escaping of shortcode attributes before they are output in pages or posts where the shortcode is embedded. This security flaw has been assigned CWE-79 (Improper Neutralization of Input During Web Page Generation). The vulnerability has received a CVSS v3.1 base score of 6.5 (Medium) from Patchstack and 5.4 (Medium) from NIST NVD, with the vector string CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N (NVD).

The vulnerability allows users with contributor-level privileges and above to perform Stored Cross-Site Scripting attacks. This could enable malicious actors to inject harmful scripts, including redirects, advertisements, and other HTML payloads that would execute when visitors access the affected site (Patchstack).

The vulnerability has been fixed in version 1.0.86 of the Amelia plugin. Users are advised to update to this version or later to remediate the security issue. Additionally, Patchstack has issued a virtual patch to mitigate this issue by blocking potential attacks until users can update to the fixed version (Patchstack).