CVE-2022-42147 is a medium-severity Cross Site Scripting (XSS) vulnerability affecting kkFileView version 4.0, specifically within the Filecontroller.java component. XSS vulnerabilities arise when an application does not properly sanitize user-supplied input, allowing attackers to inject malicious scripts into web pages viewed by other users. In this case, the vulnerability exists in the controller handling file operations, which likely processes user input related to file names or paths without adequate validation or encoding. The CVSS 3.1 base score of 6.1 reflects that the vulnerability can be exploited remotely over the network (AV:N) with low attack complexity (AC:L), requires no privileges (PR:N), but does require user interaction (UI:R), such as a victim clicking a crafted link or opening a malicious file. The scope is changed (S:C), indicating that exploitation can affect resources beyond the vulnerable component, and the impact is limited to low confidentiality and integrity loss (C:L/I:L) with no impact on availability (A:N). Although no known exploits are reported in the wild, the vulnerability is publicly disclosed and could be leveraged for session hijacking, defacement, or delivering further malware payloads through script execution in the victim's browser. The lack of vendor or product information beyond kkFileView 4.0 limits detailed contextual analysis, but the CWE-79 classification confirms the nature of the XSS issue. No patches or mitigations are currently linked, suggesting that users of kkFileView 4.0 should be cautious and consider defensive measures.

For European organizations using kkFileView 4.0, this XSS vulnerability poses a risk primarily to confidentiality and integrity of user sessions and data accessed via the vulnerable web interface. Attackers could exploit this flaw to execute arbitrary JavaScript in the context of authenticated users, potentially stealing session tokens, performing actions on behalf of users, or injecting malicious content that could spread malware or conduct phishing attacks. This is particularly concerning for organizations handling sensitive or regulated data, such as financial institutions, healthcare providers, or government agencies, where data leakage or unauthorized actions could lead to compliance violations under GDPR and other regulations. The requirement for user interaction means that social engineering or phishing campaigns could be used to trigger exploitation, increasing the risk in environments with less security awareness. While availability is not directly impacted, the indirect consequences of data compromise or trust erosion could be significant. The absence of known exploits in the wild reduces immediate urgency but does not eliminate the threat, especially as attackers often weaponize disclosed vulnerabilities over time.

1. Immediate mitigation should include implementing strict input validation and output encoding on all user-supplied data processed by the Filecontroller.java component to neutralize malicious scripts. 2. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in the browser context. 3. Educate users to be cautious about clicking on untrusted links or opening suspicious files, reducing the likelihood of successful user interaction exploitation. 4. Monitor web application logs for unusual requests or patterns indicative of attempted XSS attacks. 5. If possible, isolate kkFileView instances behind web application firewalls (WAFs) configured to detect and block XSS payloads. 6. Engage with the kkFileView community or vendor to obtain or request patches or updates addressing this vulnerability. 7. Consider deploying runtime application self-protection (RASP) solutions to detect and block exploitation attempts in real time. 8. Regularly review and update security policies and incident response plans to include scenarios involving XSS exploitation.