CVE-2023-53944 is a path traversal vulnerability identified in EasyPHP Webserver version 14.1. The flaw arises from improper limitation of pathnames to restricted directories, allowing remote attackers with low privileges to bypass the SecurityManager's intended restrictions. By sending GET requests containing encoded directory traversal sequences such as /..%5c..%5c (which correspond to ../.. in URL encoding), attackers can navigate outside the designated document root directory. This enables unauthorized reading of arbitrary files on the underlying system, including sensitive configuration files like /windows/win.ini. The vulnerability does not require user interaction or authentication, making it remotely exploitable over the network. The CVSS 4.0 vector (AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N) reflects a high-severity issue with network attack vector, low attack complexity, no privileges required beyond low-level access, and no user interaction. The impact is primarily on confidentiality, as attackers can read files that may contain sensitive information, potentially aiding further attacks or data exfiltration. Although no public exploits are currently known, the vulnerability's nature and ease of exploitation make it a significant risk. The vulnerability affects only version 14.1 of EasyPHP Webserver, and no official patches or mitigation links are currently provided in the source data. The SecurityManager component's failure to properly sanitize or restrict path traversal sequences is the root cause. This vulnerability underscores the importance of robust input validation and path normalization in webserver software to prevent directory traversal attacks.

For European organizations, the primary impact of CVE-2023-53944 is unauthorized disclosure of sensitive files on servers running EasyPHP Webserver 14.1. This can lead to leakage of configuration files, credentials, or other sensitive data that may facilitate further compromise or lateral movement within networks. Organizations in sectors such as software development, SMEs, and hosting providers that use EasyPHP as a lightweight webserver are at particular risk. Exposure of system files could also reveal information about the underlying operating system and environment, aiding attackers in crafting targeted attacks. Given the vulnerability requires only low privileges and no user interaction, attackers can exploit it remotely with relative ease, increasing the risk of widespread exploitation if the vulnerability becomes publicly known. The lack of known exploits in the wild currently reduces immediate risk but does not eliminate the threat. Additionally, the vulnerability could be leveraged as a stepping stone for more complex attacks, including privilege escalation or deployment of malware. The impact on availability and integrity is minimal, but confidentiality breaches alone justify urgent remediation. European data protection regulations such as GDPR may impose legal and financial consequences if sensitive data is exposed due to this vulnerability.

To mitigate CVE-2023-53944, European organizations should first verify if they are running EasyPHP Webserver version 14.1 and plan immediate upgrades once patches become available. In the absence of official patches, organizations should implement strict network-level controls to limit access to the EasyPHP Webserver, such as IP whitelisting and segmentation. Deploy web application firewalls (WAFs) configured to detect and block directory traversal patterns, including encoded sequences like %5c and %2e%2e, to prevent exploitation attempts. Review and harden SecurityManager configurations to ensure proper path normalization and restriction enforcement. Conduct regular log monitoring and alerting for suspicious GET requests containing traversal sequences. Consider replacing EasyPHP Webserver with more secure and actively maintained webserver software if feasible. Additionally, educate developers and administrators about the risks of path traversal vulnerabilities and the importance of input validation. Implement file system permissions to restrict the webserver process from reading sensitive files outside the document root. Finally, maintain an incident response plan to quickly address any exploitation attempts or breaches resulting from this vulnerability.