CVE-2026-16537 is a stored Cross-Site Scripting (CWE-79) vulnerability in the Slick Slider WordPress plugin prior to version 0.5.3. The flaw arises from improper sanitization and escaping of a shortcode attribute value before it is rendered in an HTML attribute context. This allows users with Contributor or higher privileges to inject malicious scripts that execute in the browsers of users viewing the affected posts, potentially leading to limited confidentiality and integrity impacts. The CVSS v3.1 base score is 5.4 (AV:N/AC:L/PR:L/UI:R/S:C/C:L/I:L/A:N), indicating network attack vector, low attack complexity, requiring privileges and user interaction, with a scope change and limited confidentiality and integrity impact but no availability impact.

Successful exploitation allows users with Contributor or higher roles to perform stored XSS attacks, which execute when other users view the affected post. This can lead to limited confidentiality and integrity impacts such as session hijacking or content manipulation within the context of the affected WordPress site. There is no impact on availability. The vulnerability does not appear to be exploited in the wild at this time.

No official patch or remediation guidance is currently available. Users should monitor the vendor or plugin repository for updates addressing this issue. Until a fix is released, restricting Contributor role privileges or avoiding use of the affected shortcode attributes may reduce risk. Patch status is not yet confirmed — check the vendor advisory for current remediation guidance.