CVE-2013-4102 in Cryptocat
Summary
by MITRE
Cryptocat before 2.1.12 has a strophe.js Math.random() Function Random Number Generator Weakness
VulDB is the best source for vulnerability data and more expert information about this specific topic.
Analysis
by VulDB Data Team • 02/01/2024
The vulnerability identified as CVE-2013-4102 affects the Cryptocat messaging application version 2.1.11 and earlier, specifically targeting the strophe.js library component that handles XMPP communication. This weakness stems from the use of the Math.random() function as a source for generating cryptographic randomness within the application's security mechanisms. The flaw represents a significant weakness in the application's cryptographic implementation that directly impacts the security of encrypted communications between users.
The technical root cause of this vulnerability lies in the predictable nature of JavaScript's Math.random() function, which is not cryptographically secure and produces pseudo-random numbers that can be easily predicted or reverse-engineered. When Cryptocat relied on this function for generating cryptographic keys, nonces, or other security-critical random values, it created a scenario where adversaries could potentially reconstruct the random sequences used in the encryption process. This weakness is classified under CWE-330 as the use of insufficiently random values in cryptographic contexts, specifically manifesting as weak random number generation that undermines the security of cryptographic operations.
The operational impact of this vulnerability extends beyond simple predictability issues, as it fundamentally compromises the confidentiality and integrity of communications within the Cryptocat application. An attacker who can predict or reproduce the random sequences used for encryption keys could potentially decrypt communications, impersonate users, or perform man-in-the-middle attacks against the messaging system. This weakness directly affects the application's core security promise of providing end-to-end encrypted messaging, making it vulnerable to attacks that would normally be prevented by proper cryptographic randomization. The vulnerability is particularly concerning because it affects the foundational cryptographic operations that protect user communications from eavesdropping and tampering.
Mitigation strategies for this vulnerability require immediate patching of the Cryptocat application to version 2.1.12 or later, which addresses the weak random number generation issue by implementing proper cryptographic random number generation functions. Organizations should also consider implementing additional security measures such as monitoring for unusual network traffic patterns that might indicate exploitation attempts, conducting regular security audits of cryptographic implementations, and ensuring that all third-party libraries used in security-critical applications undergo proper security review. The fix should involve replacing the Math.random() calls with cryptographically secure random number generators such as the Web Crypto API's crypto.getRandomValues() function or equivalent secure alternatives that provide unpredictable outputs suitable for cryptographic use cases. This vulnerability serves as a reminder of the critical importance of using cryptographically secure random number generation in security-sensitive applications and aligns with ATT&CK technique T1552.004 for unsecured credentials and T1071.004 for application layer protocol traffic.