CVE-2025-41351 in Cloud Server
Summary
by MITRE • 01/28/2026
Vulnerability that allows a Padding Oracle Attack to be performed on the Funambol v30.0.0.20 cloud server. The thumbnail display URL allows an attacker to decrypt and encrypt the parameters used by the application to generate ‘self-signed’ access URLs.
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Analysis
by VulDB Data Team • 01/28/2026
The vulnerability identified as CVE-2025-41351 represents a critical padding oracle attack susceptibility within the Funambol v30.0.0.20 cloud server implementation. This security flaw specifically targets the application's handling of thumbnail display URLs, which serve as the attack vector for unauthorized decryption and encryption of parameters used in generating self-signed access URLs. The vulnerability stems from improper implementation of cryptographic padding validation mechanisms within the server's parameter processing pipeline, creating an exploitable condition where attackers can systematically determine the original plaintext values through carefully crafted oracle queries.
The technical exploitation of this vulnerability follows established padding oracle attack patterns that have been documented in cybersecurity literature and classified under CWE-119 as improper restriction of operations within a recognized security boundary. The attack leverages the server's response behavior when processing malformed padding in encrypted parameters, allowing an attacker to iteratively query the system and deduce the complete encrypted payload through statistical analysis and pattern recognition. This particular implementation flaw affects the Funambol server's cryptographic operations during thumbnail URL generation, where the self-signed access URLs rely on parameter encryption for access control and session management.
The operational impact of this vulnerability extends beyond simple information disclosure, as it enables sophisticated attackers to potentially manipulate access controls and gain unauthorized access to protected resources within the Funambol cloud environment. The ability to decrypt and re-encrypt parameters means that an attacker could forge valid access tokens, bypass authentication mechanisms, and potentially access restricted content or functionality. This vulnerability directly impacts the integrity and confidentiality of the application's security model, particularly affecting the server's ability to maintain proper access control boundaries as defined in the NIST SP 800-53 security framework. The attack requires minimal privileges and can be executed remotely, making it particularly dangerous in cloud environments where such applications are exposed to external networks.
Mitigation strategies for this vulnerability should prioritize immediate implementation of proper cryptographic padding validation mechanisms that do not leak information through timing or error response variations. The recommended approach includes implementing authenticated encryption modes such as AES-GCM or ChaCha20-Poly1305, which provide both confidentiality and integrity protection without the padding oracle attack surface. Additionally, the server should be configured to return consistent error responses regardless of padding validity, preventing attackers from distinguishing between different types of cryptographic failures. Network segmentation and access controls should be enforced to limit exposure of the vulnerable application components, while regular security assessments should validate the effectiveness of implemented cryptographic protections. This vulnerability demonstrates the importance of following established security guidelines such as those outlined in the OWASP Cryptographic Storage Cheat Sheet and the NIST Cybersecurity Framework for maintaining secure application development practices.