CVE-2026-0588 is a cross-site scripting vulnerability identified in Xinhu Rainrock RockOA, a web-based office automation platform, affecting versions up to 2.7.1. The vulnerability resides in the API component, specifically in the rockfun.php file, where the 'callback' parameter is improperly handled, allowing an attacker to inject malicious JavaScript code. This flaw enables remote attackers to craft malicious requests that, when executed by a victim's browser, can lead to the execution of arbitrary scripts within the context of the vulnerable application. The attack vector is network accessible without requiring authentication, but user interaction is necessary, such as clicking on a malicious link or visiting a crafted webpage. The vulnerability can compromise confidentiality and integrity by enabling session hijacking, credential theft, or unauthorized actions performed on behalf of the user. The vendor was notified but has not responded or issued a patch, and no public exploits are currently reported in the wild. The CVSS 4.0 base score is 5.1, reflecting medium severity due to ease of exploitation and potential impact. The lack of vendor response increases risk as organizations must implement their own mitigations. This vulnerability highlights the importance of proper input validation and output encoding in web applications, especially for parameters used in dynamic script contexts.

For European organizations using Xinhu Rainrock RockOA, this vulnerability poses a moderate risk. Successful exploitation could lead to unauthorized access to sensitive information, session hijacking, and potential lateral movement within internal networks if attackers gain elevated privileges through stolen credentials. Organizations in sectors such as government, finance, and critical infrastructure that rely on RockOA for internal communications and workflow automation could face operational disruptions and data breaches. The remote and unauthenticated nature of the attack increases the attack surface, especially for publicly accessible RockOA instances. However, the requirement for user interaction somewhat limits automated mass exploitation. The absence of vendor patches means organizations must rely on internal controls and monitoring to mitigate risk. Additionally, the public availability of exploit details could increase attempts to exploit this vulnerability, raising the urgency for European entities to address it promptly.

1. Implement strict input validation and output encoding on the 'callback' parameter within rockfun.php to neutralize malicious script injections. 2. Apply web application firewalls (WAFs) with custom rules to detect and block suspicious requests targeting the vulnerable parameter. 3. Restrict access to the RockOA API endpoints to trusted internal networks or VPNs to reduce exposure. 4. Educate users about the risks of clicking unknown or suspicious links to reduce the likelihood of successful user interaction exploitation. 5. Monitor web server and application logs for anomalous requests containing suspicious callback parameter values. 6. If possible, isolate or sandbox the RockOA application to limit the impact of a successful XSS attack. 7. Engage with Xinhu vendor or community to advocate for an official patch or update. 8. Consider deploying Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing RockOA. 9. Regularly review and update incident response plans to include scenarios involving XSS exploitation.