CVE-2013-0294 in pyrad
Summary
by MITRE
packet.py in pyrad before 2.1 uses weak random numbers to generate RADIUS authenticators and hash passwords, which makes it easier for remote attackers to obtain sensitive information via a brute force attack.
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Analysis
by VulDB Data Team • 06/11/2024
The vulnerability identified as CVE-2013-0294 resides within the pyrad library version 2.1 and earlier, specifically affecting the packet.py module responsible for RADIUS protocol implementation. This flaw represents a critical weakness in cryptographic randomness implementation that directly impacts the security of authentication mechanisms relying on RADIUS protocol. The vulnerability stems from the use of weak random number generation functions that fail to provide adequate entropy for cryptographic purposes, creating predictable sequences that adversaries can exploit to compromise authentication processes.
The technical flaw manifests in how pyrad generates RADIUS authenticators and hash passwords during authentication exchanges. When the library employs weak random number generators instead of cryptographically secure ones, it produces sequences that exhibit patterns or predictable values. This weakness allows attackers to perform brute force attacks against the generated authenticators, which are used to verify the integrity of RADIUS packets and authenticate users. The predictable nature of these values significantly reduces the search space required for successful attacks, making unauthorized access more feasible than it should be under proper cryptographic practices.
The operational impact of this vulnerability extends beyond simple authentication bypasses, as it fundamentally undermines the security model of RADIUS-based authentication systems. Remote attackers can leverage this weakness to impersonate legitimate users, gain unauthorized network access, or conduct man-in-the-middle attacks against RADIUS servers. The vulnerability affects any system using pyrad version 2.1 or earlier for RADIUS protocol implementation, including network access servers, authentication servers, and wireless network infrastructure components that rely on RADIUS for user verification. This weakness creates persistent security risks that can remain undetected for extended periods, as the predictable nature of weak randomness may not immediately manifest in obvious system behavior.
Organizations should prioritize immediate remediation by upgrading to pyrad version 2.1 or later, which addresses the weak random number generation issue through proper implementation of cryptographic random number generators. System administrators should also conduct comprehensive audits of all RADIUS-based authentication systems to identify potential exploitation vectors and implement additional monitoring controls to detect unusual authentication patterns. The vulnerability aligns with CWE-330, which addresses the use of insufficiently random values in cryptographic contexts, and maps to ATT&CK technique T1110.003 for credential access through brute force methods, highlighting the need for both immediate patching and ongoing security monitoring to prevent exploitation attempts.
Additional mitigation strategies include implementing network segmentation to limit access to RADIUS servers, deploying intrusion detection systems to monitor for suspicious authentication patterns, and establishing regular security assessments to identify other potential weaknesses in authentication infrastructure. The vulnerability demonstrates the critical importance of proper cryptographic implementation in network security protocols and underscores the necessity of using well-vetted cryptographic libraries that provide adequate entropy for security-sensitive operations. Organizations must also consider the broader implications of weak random number generation in their security infrastructure and ensure that all cryptographic components meet established security standards and best practices for their respective applications.