CVE-2025-41035 is a high-severity path traversal vulnerability identified in appRain CMF version 4.0.5. The vulnerability arises from improper limitation of a pathname to a restricted directory (CWE-22) in the /apprain/common/download/ endpoint. Specifically, authenticated users with adequate permissions can exploit this flaw by manipulating a base64-encoded path parameter after the /download/ segment to bypass the SecurityManager restrictions. This allows them to download arbitrary files located outside the web server's document root. The vulnerability does not require user interaction and can be exploited remotely over the network. The CVSS 4.0 vector (7.1) indicates network attack vector (AV:N), low attack complexity (AC:L), no user interaction (UI:N), and privileges required (PR:L), with high impact on confidentiality (VC:H) but no impact on integrity or availability. The flaw essentially allows an attacker with limited privileges to access sensitive files on the server that should be inaccessible, potentially exposing configuration files, credentials, source code, or other sensitive data. Although no known exploits are currently reported in the wild, the vulnerability represents a significant risk due to the ease of exploitation and the potential sensitivity of exposed information. The lack of an official patch at the time of disclosure further increases the urgency for mitigation. This vulnerability is specific to appRain CMF 4.0.5, a content management framework used to build web applications, meaning that organizations using this version are directly at risk.

For European organizations using appRain CMF 4.0.5, this vulnerability poses a substantial risk to confidentiality. Attackers with authenticated access can retrieve sensitive files outside the intended directory, potentially exposing personal data, intellectual property, or internal configuration details. This could lead to data breaches, regulatory non-compliance (e.g., GDPR violations), and reputational damage. Since the vulnerability does not affect integrity or availability directly, the primary concern is unauthorized data disclosure. However, exposed files could facilitate further attacks, such as privilege escalation or lateral movement within the network. The requirement for authentication limits exposure to insiders or compromised accounts, but given the low complexity of exploitation and network accessibility, the threat remains significant. European organizations in sectors with strict data protection requirements, such as finance, healthcare, and government, are particularly vulnerable to the consequences of such data leaks.

1. Immediate mitigation should include restricting access to the /apprain/common/download/ endpoint to only trusted and necessary users, implementing strict access controls and monitoring for unusual download activity. 2. Employ web application firewalls (WAFs) with custom rules to detect and block suspicious base64-encoded path traversal attempts targeting the download endpoint. 3. Review and harden authentication and authorization mechanisms to ensure that only users with legitimate permissions can access sensitive functionality. 4. Conduct a thorough audit of server file permissions and remove or restrict access to sensitive files that do not need to be accessible by the web application. 5. If possible, upgrade to a patched version of appRain CMF once available; until then, consider disabling or isolating the vulnerable download functionality. 6. Implement logging and alerting for any access to files outside the document root to detect potential exploitation attempts early. 7. Educate administrators and developers about secure coding practices to prevent similar path traversal issues in custom extensions or configurations.