CVE-2026-112845 in Off-Canvas Sidebars & Menus Plugin
Summary
by MITRE • 10/22/2026
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') vulnerability in Jory Hogeveen Off-Canvas Sidebars & Menus (Slidebars) off-canvas-sidebars allows Stored XSS.This issue affects Off-Canvas Sidebars & Menus (Slidebars): from n/a through 0.5.9.
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Analysis
by VulDB Data Team • 10/22/2026
The identified vulnerability represents a classic instance of Improper Neutralization of Input During Web Page Generation, commonly known as Cross-Site Scripting or XSS. Specifically, this is classified under CWE-79 in the Common Weakness Enumeration framework, which addresses flaws where user-controllable input is not properly validated before being included in web pages sent to other users. In the context of the Off-Canvas Sidebars & Menus plugin by Jory Hogeveen, also referred to as Slidebars, this flaw manifests as a Stored XSS vulnerability within versions ranging from n/a through 0.5.9. Unlike reflected XSS where malicious scripts are executed immediately upon request, stored XSS involves the persistence of the malicious payload on the target server, typically in a database or content management system field, leading to execution every time the affected page is loaded by any user who views it.
The technical root cause lies in the insufficient sanitization and validation mechanisms applied to input fields that are rendered within the off-canvas sidebar interface. When an administrator or authorized user inputs data into these configuration areas, such as menu labels, descriptions, or custom HTML content, the application fails to strip out potentially executable script tags or event handlers before storing them. Consequently, when a visitor accesses the website and triggers the display of the off-canvas menu, the browser interprets the stored malicious code as part of the page's legitimate DOM structure. This allows an attacker who has write access to these fields to inject JavaScript payloads that execute in the context of the victim’s session with the target domain.
From a tactical perspective, this vulnerability aligns with several techniques within the MITRE ATT&CK framework for enterprise security. It is primarily associated with T1059, Command and Scripting Interpreter, specifically through web browser scripting mechanisms like JavaScript. Furthermore, because stored XSS often targets administrative interfaces or content that influences all visitors, it facilitates T1078, Valid Accounts, if the attacker uses stolen credentials to inject the payload, and potentially T1213, Data from Information Repositories, if the script exfiltrates data such as cookies, session tokens, or sensitive form inputs. The persistent nature of stored XSS makes it particularly dangerous for content management systems where multiple users may interact with the same interface over time.
The operational impact of this vulnerability is severe and multifaceted. For end-users visiting the site, successful exploitation can lead to account hijacking through session cookie theft, allowing attackers to impersonate legitimate users or administrators. It also enables phishing attacks by dynamically altering page content to mimic login forms or other trusted interfaces, thereby stealing credentials directly from unsuspecting visitors. Additionally, attackers can deface websites, redirect traffic to malicious domains hosting malware, or use the victim’s browser as a proxy for further network reconnaissance and attacks against internal resources if cross-origin restrictions are bypassed via specific vector combinations. The trust relationship between the user and the website is fundamentally compromised, leading to potential data breaches and reputational damage for site owners.
Mitigation strategies must address both immediate remediation and long-term security hygiene. The most effective solution is to upgrade the Off-Canvas Sidebars & Menus plugin to a version later than 0.5.9 where this vulnerability has been patched by implementing robust input validation and output encoding. Developers should ensure that all user-supplied data is strictly validated against expected formats using allowlists rather than blocklists, which are prone to bypasses. Furthermore, strict output encoding must be applied when rendering any dynamic content into HTML contexts to prevent the browser from interpreting it as executable code. Implementing Content Security Policy headers can also serve as a defense-in-depth measure by restricting the sources from which scripts can be loaded and executed, thereby mitigating the impact of successful XSS attempts even if input sanitization fails. Regular security audits and penetration testing focused on web application vulnerabilities are recommended to identify similar weaknesses in other plugins or custom code within the WordPress ecosystem.