CVE-2022-4957 is a cross-site scripting (XSS) vulnerability identified in the librespeed speedtest application, specifically affecting versions 5.2.0 through 5.2.4. The vulnerability resides in the results/stats.php file, where improper sanitization of the 'id' parameter allows an attacker to inject malicious scripts. This vulnerability is classified under CWE-79, which pertains to improper neutralization of input during web page generation, leading to XSS attacks. An attacker can exploit this remotely by manipulating the 'id' argument in HTTP requests to execute arbitrary JavaScript in the context of the victim's browser. The vulnerability requires low privileges (PR:L) and user interaction (UI:R), meaning the attacker must trick a user into clicking a crafted link or visiting a malicious page. The CVSS 3.1 base score is 3.5, indicating a low severity primarily due to the limited impact on confidentiality and availability, and the requirement for user interaction and privileges. The integrity impact is low, as the attacker can execute scripts but cannot directly alter server-side data. No known exploits are currently reported in the wild. The issue is addressed in version 5.2.5 of librespeed speedtest, with a patch identified by commit a85f2c086f3449dffa8fe2edb5e2ef3ee72dc0e9. Organizations using affected versions should upgrade promptly to mitigate this risk.

For European organizations, the impact of this XSS vulnerability is generally low but should not be underestimated. Successful exploitation could allow attackers to perform actions such as session hijacking, phishing, or delivering malicious payloads to users interacting with the speedtest application. This could lead to compromised user accounts or unauthorized actions within the application context. While the vulnerability does not directly affect system confidentiality or availability, it can be a stepping stone for more sophisticated attacks, especially if the speedtest service is integrated into broader network monitoring or diagnostic platforms. Organizations relying on librespeed speedtest for internal or customer-facing services may face reputational damage if users are targeted via this vulnerability. Additionally, regulatory frameworks such as GDPR require organizations to maintain secure processing environments; failure to patch known vulnerabilities could lead to compliance issues. Given that the attack requires user interaction and some privilege level, the risk is mitigated but still present, particularly in environments with less security awareness or where the speedtest is publicly accessible.

1. Immediate upgrade to librespeed speedtest version 5.2.5 or later, which contains the patch addressing this vulnerability. 2. Implement strict input validation and output encoding on all user-supplied inputs, especially parameters like 'id' in results/stats.php, to prevent script injection. 3. Employ Content Security Policy (CSP) headers to restrict the execution of unauthorized scripts in browsers accessing the speedtest application. 4. Conduct user awareness training to reduce the likelihood of users clicking on suspicious links that could exploit this vulnerability. 5. Monitor web application logs for unusual parameter values or repeated attempts to inject scripts via the 'id' parameter. 6. If upgrading immediately is not feasible, consider restricting access to the speedtest application to trusted internal networks or authenticated users only, reducing exposure. 7. Regularly review and update web application security configurations and perform periodic vulnerability assessments to detect similar issues proactively.