CVE-2022-36098 is a cross-site scripting (XSS) vulnerability affecting the XWiki Platform, specifically within the Mentions UI component used for tagging users in wiki content. The vulnerability exists in versions starting from 12.5-rc-1 up to but not including 13.10.6, and from 14.0 up to but not including 14.4. The root cause is improper neutralization of input during web page generation (CWE-79), allowing an attacker to inject and store malicious JavaScript or Groovy scripts in mention fields, macro anchors, or reference fields. When a user visits a page containing such a mention, the stored script executes in their browser context, potentially leading to session hijacking, unauthorized actions, or data theft. This is a stored XSS vulnerability, meaning the malicious payload persists on the server and affects all users viewing the compromised content. The issue has been patched in versions 13.10.6 and 14.4. As a temporary workaround, administrators can update the `XWiki.Mentions.MentionsMacro` and modify the `Macro code` field of the `XWiki.WikiMacroClass` XObject to sanitize or restrict input. There are no known exploits in the wild reported to date. The vulnerability requires no authentication to exploit if the attacker can create or edit mentions, which may depend on the wiki’s permission settings. User interaction is required only in the sense that a victim must visit the compromised page to trigger the script execution. The vulnerability impacts confidentiality, integrity, and availability by enabling script execution in the victim’s browser, potentially leading to credential theft, unauthorized actions, or further compromise of the wiki platform or connected systems.

For European organizations using the XWiki Platform, this vulnerability poses a moderate risk. XWiki is often used for internal documentation, collaboration, and knowledge management, so exploitation could lead to unauthorized access to sensitive corporate information or internal communications. Attackers could leverage the XSS to steal session cookies, impersonate users, or perform actions on behalf of users with elevated privileges, potentially leading to data leakage or disruption of business processes. The impact is heightened in organizations where the wiki is accessible to a broad user base or integrated with other internal systems. Since the vulnerability allows stored script execution, it could facilitate persistent attacks affecting multiple users over time. Additionally, if the wiki is exposed externally or used by partners, the attack surface increases. The lack of known exploits suggests limited active targeting, but the medium severity and ease of exploitation warrant prompt remediation to prevent potential future attacks. Organizations in regulated sectors (e.g., finance, healthcare) may face compliance risks if sensitive data is exposed due to this vulnerability.

1. Upgrade affected XWiki Platform instances to version 13.10.6 or 14.4 or later, where the vulnerability is patched. 2. If immediate upgrade is not feasible, apply the workaround by updating the `XWiki.Mentions.MentionsMacro` and editing the `Macro code` field of the `XWiki.WikiMacroClass` XObject to sanitize inputs and prevent script injection. 3. Review and tighten wiki permissions to restrict who can create or edit mentions, limiting the ability of untrusted users to inject malicious content. 4. Implement Content Security Policy (CSP) headers to restrict the execution of inline scripts and reduce the impact of XSS attacks. 5. Conduct regular security audits and code reviews of custom macros or extensions that interact with mentions or user input fields. 6. Educate users to be cautious when clicking on links or viewing content in the wiki, especially if unexpected or from unknown sources. 7. Monitor logs and user activity for suspicious behavior indicative of exploitation attempts. 8. Consider deploying web application firewalls (WAF) with rules tuned to detect and block XSS payloads targeting the wiki platform.