CVE-2010-3073 in EncFS
Summary
by MITRE
SSL_Cipher.cpp in EncFS before 1.7.0 does not properly handle integer data sizes when constructing headers intended for randomization of initialization vectors, which makes it easier for local users to obtain sensitive information by defeating cryptographic protection mechanisms.
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Analysis
by VulDB Data Team • 11/15/2024
The vulnerability identified as CVE-2010-3073 resides within the SSL_Cipher.cpp component of EncFS versions prior to 1.7.0, representing a critical flaw in cryptographic implementation that directly undermines the security assurances provided by the encryption system. This issue specifically targets the handling of integer data sizes during header construction processes designed to randomize initialization vectors, creating a pathway for attackers to compromise the confidentiality of encrypted data.
The technical flaw manifests in how integer data types are managed when constructing cryptographic headers intended to randomize initialization vectors within the encryption process. When integer sizes are improperly handled, the system fails to maintain the expected cryptographic randomness required for secure encryption operations. This improper handling creates predictable patterns in the initialization vectors that should otherwise remain random, allowing attackers to reverse-engineer or predict the cryptographic state and potentially extract sensitive information from encrypted files.
The operational impact of this vulnerability extends beyond simple information disclosure, as it fundamentally weakens the cryptographic protection mechanisms that EncFS is designed to provide. Local users can exploit this flaw to bypass the intended security controls, potentially gaining access to encrypted data that should remain protected. The vulnerability specifically targets the randomization aspect of encryption, which is crucial for preventing pattern analysis attacks and maintaining the security of the entire encryption system. This weakness creates a scenario where attackers can systematically work against the cryptographic protection rather than being limited to brute force approaches.
This vulnerability aligns with CWE-128, which describes "Wrap or Overflow" conditions in integer operations, and represents a classic example of how improper handling of data type sizes can create exploitable weaknesses in cryptographic implementations. The flaw also relates to ATT&CK technique T1552.004, which covers "Unsecured Credentials," as the vulnerability enables attackers to access encrypted data that should be protected by cryptographic means. The improper integer handling creates a condition where attackers can effectively defeat the cryptographic randomization that is essential for maintaining data confidentiality.
The security implications of this vulnerability are particularly severe because it affects the core cryptographic operations of EncFS, which is designed to provide secure file encryption on Linux systems. The weakness allows for systematic attacks that can bypass the intended security controls, potentially exposing sensitive information stored in encrypted files. This represents a fundamental failure in the cryptographic implementation that undermines the entire purpose of using EncFS for data protection.
Mitigation strategies for CVE-2010-3073 require immediate upgrading to EncFS version 1.7.0 or later, which contains the necessary fixes for proper integer size handling during header construction. System administrators should also implement monitoring for unauthorized local access attempts and consider additional security controls to prevent local privilege escalation. Organizations using EncFS should conduct thorough vulnerability assessments to identify any systems running affected versions and ensure complete remediation through software updates. The fix addresses the root cause by properly managing integer data sizes during cryptographic header construction, restoring the intended randomization of initialization vectors and maintaining the cryptographic security guarantees that EncFS is designed to provide.