CVE-2025-29157 is a vulnerability identified in the petstore application version 1.0.7. The issue arises when a remote attacker accesses a non-existent endpoint, specifically /cart, which triggers the server to return a 404 error page. Instead of a generic error message, the server discloses sensitive information including the Servlet name (default) and the server version. This information disclosure can aid attackers in fingerprinting the server environment, potentially facilitating further targeted attacks such as exploitation of known vulnerabilities tied to the disclosed server version or servlet container. While the vulnerability itself does not directly allow code execution, the exposure of internal server details increases the attack surface and can be leveraged in multi-stage attacks. The vulnerability is triggered remotely without authentication or user interaction, making it accessible to any attacker who can reach the server. No CVSS score is currently assigned, and no patches or known exploits in the wild have been reported yet. The lack of patch links suggests that remediation may require configuration changes or updates from the vendor. The vulnerability highlights improper error handling and information leakage through verbose error messages, a common security weakness that can undermine the confidentiality and integrity of the system by aiding attackers in reconnaissance and subsequent exploitation.

For European organizations using petstore v1.0.7, this vulnerability poses a moderate risk primarily through information disclosure. The exposure of server version and servlet details can enable attackers to tailor attacks exploiting other vulnerabilities specific to the disclosed software versions. This can lead to potential unauthorized access, data breaches, or service disruption if combined with other exploits. Organizations in sectors with high-value data or critical operations (e.g., finance, healthcare, government) may face increased risk if attackers leverage this information for advanced persistent threats or targeted attacks. Additionally, the vulnerability could undermine compliance with European data protection regulations such as GDPR, which mandates safeguarding system confidentiality and integrity. Although no direct code execution or denial of service is reported, the vulnerability facilitates reconnaissance that can be a precursor to more severe attacks, thus impacting the overall security posture of affected organizations.

European organizations should implement the following specific mitigations: 1) Review and harden error handling mechanisms to ensure that error pages do not disclose sensitive server information. This can be done by customizing 404 error pages to display generic messages without revealing server or servlet details. 2) Apply any available updates or patches from the petstore vendor as soon as they are released. 3) Conduct a thorough inventory of all petstore application instances and verify their versions to identify and prioritize vulnerable deployments. 4) Employ web application firewalls (WAFs) to detect and block suspicious requests targeting non-existent endpoints or attempting to enumerate server details. 5) Limit external exposure of the petstore application by restricting access through network segmentation or VPNs where feasible. 6) Monitor server logs for unusual access patterns to non-existent endpoints that may indicate reconnaissance attempts. 7) Regularly perform security assessments and penetration testing focusing on error handling and information leakage vectors. These measures go beyond generic advice by focusing on error page customization, proactive monitoring, and network-level controls tailored to this vulnerability.