CVE-2013-4103 in Cryptocat
Summary
by MITRE
Cryptocat before 2.1.12 has Remote Script Injection due to improperly sanitizing user input
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Analysis
by VulDB Data Team • 12/21/2024
The vulnerability identified as CVE-2013-4103 affects Cryptocat versions prior to 2.1.12 and represents a critical remote script injection flaw that undermines the security of end-to-end encrypted communications. This vulnerability stems from inadequate input sanitization mechanisms within the application's processing of user-provided data, creating a pathway for malicious actors to inject arbitrary scripts into the application's execution environment. The flaw specifically manifests when the application fails to properly validate and sanitize user input before incorporating it into dynamic content or execution contexts, thereby exposing the system to cross-site scripting attacks that can compromise user sessions and data integrity.
The technical implementation of this vulnerability allows attackers to exploit the insufficient sanitization routines by crafting malicious input that bypasses the application's security controls. When user data is improperly handled, it can be executed as script code within the browser context of other users who encounter the malicious content. This type of vulnerability falls under the Common Weakness Enumeration category CWE-79, which specifically addresses Cross-Site Scripting flaws, and represents a direct violation of secure coding practices that require proper input validation and output encoding. The vulnerability operates at the application layer and can be exploited through various vectors including message content, user profiles, or any input field where user-generated content is processed and displayed without adequate sanitization.
The operational impact of CVE-2013-4103 extends beyond simple script execution, as it fundamentally compromises the security assurances that Cryptocat users expect from an encrypted messaging platform. Attackers can leverage this vulnerability to steal session cookies, redirect users to malicious sites, or execute arbitrary commands within the context of other users' browsers. The implications are particularly severe given that Cryptocat is designed for secure communications, making this vulnerability especially dangerous as it undermines the very foundation of trust that users place in the application's security model. The attack surface is broad as it affects any user interaction within the application that involves user-generated content processing, potentially exposing all users to persistent threats that can persist across multiple sessions.
Mitigation strategies for this vulnerability require immediate implementation of comprehensive input sanitization and output encoding mechanisms throughout the application's codebase. Security patches should include robust validation routines that filter and escape user input before processing, implementing both server-side and client-side protections to prevent script injection attempts. Organizations should deploy proper content security policies to limit script execution contexts and establish strict input validation controls that align with secure coding guidelines. The remediation process must address all input vectors where user data is processed, including message handling, user profile management, and any dynamic content generation features. Additionally, regular security assessments and code reviews should be implemented to prevent similar vulnerabilities from emerging in future versions, with particular attention to the ATT&CK framework's T1211 technique for exploiting input validation weaknesses in web applications.