CVE-2022-42748 is a reflected cross-site scripting (XSS) vulnerability identified in CandidATS version 3.0.0, specifically affecting the 'sortDirection' parameter of the 'ajax.php' resource. This vulnerability arises because the application fails to properly validate or sanitize user-supplied input before reflecting it back in the web response. An attacker can exploit this flaw by crafting a malicious URL or request that includes executable JavaScript code within the 'sortDirection' parameter. When a victim user accesses this crafted URL, the malicious script executes in their browser context, enabling the attacker to steal sensitive information such as session cookies. The stolen cookies can then be used to hijack user sessions, potentially allowing unauthorized access to the victim's account or sensitive data within the CandidATS application. The CVSS 3.1 base score for this vulnerability is 6.1, indicating a medium severity level. The vector string (AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N) shows that the attack is network exploitable without privileges and requires user interaction (clicking a malicious link). The scope is changed, meaning the vulnerability can affect resources beyond the vulnerable component. The impact affects confidentiality and integrity but not availability. No known exploits in the wild have been reported, and no official patches or fixes have been linked, suggesting that organizations using CandidATS 3.0.0 remain at risk if unmitigated. The vulnerability is classified under CWE-79, which is the standard category for cross-site scripting issues.

For European organizations using CandidATS 3.0.0, this vulnerability poses a significant risk to user session security and data confidentiality. Attackers exploiting this XSS flaw can hijack user sessions by stealing cookies, potentially gaining unauthorized access to sensitive recruitment or applicant tracking data managed within CandidATS. This could lead to data breaches involving personal identifiable information (PII) of job applicants or internal HR data, which is subject to strict data protection regulations such as the GDPR. The integrity of user interactions and data could also be compromised, undermining trust in the application. While availability is not directly impacted, the reputational damage and regulatory consequences of a data breach could be severe. The requirement for user interaction (clicking a malicious link) means that phishing or social engineering campaigns could be used to deliver the exploit, increasing the attack surface. Given the lack of patches, organizations may remain vulnerable unless mitigations are applied. The medium severity rating suggests that while the vulnerability is serious, it is not trivially exploitable without user action and does not allow full system compromise.

To mitigate CVE-2022-42748, European organizations should implement multiple layers of defense beyond waiting for an official patch. First, apply strict input validation and output encoding on the 'sortDirection' parameter within CandidATS if source code access or configuration options allow customization. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers, which can significantly reduce the impact of reflected XSS attacks. Educate users and administrators about the risks of clicking untrusted links, especially those purporting to be related to recruitment or HR activities. Utilize web application firewalls (WAFs) with rules designed to detect and block reflected XSS payloads targeting the vulnerable parameter. Monitor application logs and network traffic for suspicious requests containing script tags or unusual parameter values. If possible, isolate the CandidATS application within a segmented network zone to limit lateral movement in case of compromise. Finally, maintain an inventory of affected systems and plan for an upgrade or patch deployment once available, coordinating with vendors or community sources for updates.