CVE-2013-4100 in Cryptocat
Summary
by MITRE
Cryptocat before 2.0.22 has Remote Denial of Service via username
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Analysis
by VulDB Data Team • 02/01/2024
The vulnerability identified as CVE-2013-4100 affects Cryptocat versions prior to 2.0.22 and represents a remote denial of service flaw that can be exploited through manipulation of the username parameter. This issue demonstrates a critical weakness in the application's input validation mechanisms, where improper handling of user-provided data leads to system instability and service disruption. The vulnerability specifically targets the client-side application used for secure instant messaging, making it particularly concerning given the sensitive nature of communications it facilitates. The flaw exists within the protocol handling layer where usernames are processed during connection establishment and authentication phases.
The technical implementation of this vulnerability stems from inadequate bounds checking and input sanitization within the Cryptocat client software. When a malicious user provides a specially crafted username string, the application fails to properly validate the input length or content, causing memory corruption or stack overflow conditions that result in application termination. This type of vulnerability falls under CWE-129, which encompasses improper validation of input length, and aligns with ATT&CK technique T1499.004 for network denial of service attacks. The vulnerability is particularly dangerous because it requires no authentication or special privileges to exploit, making it accessible to any remote attacker who can establish a connection to the target system.
The operational impact of this vulnerability extends beyond simple service disruption, as it can be leveraged to create persistent availability issues for users of the Cryptocat messaging platform. Attackers can repeatedly exploit this flaw to force disconnections, prevent legitimate users from accessing secure communications, and potentially disrupt entire communication channels within organizations relying on the software. The vulnerability affects the core functionality of the application, as the denial of service occurs during the initial connection phase, preventing users from establishing secure chat sessions. This attack vector specifically targets the client-side implementation and can be executed through various network access points, including public chat servers that Cryptocat users might connect to, making it a significant concern for organizations that depend on secure messaging solutions.
Mitigation strategies for this vulnerability require immediate patching of the Cryptocat client software to version 2.0.22 or later, which includes proper input validation and bounds checking mechanisms. Network administrators should also implement monitoring solutions to detect unusual connection patterns or malformed username inputs that might indicate exploitation attempts. The fix typically involves implementing strict input length limitations, character set validation, and proper memory management practices to prevent buffer overflows. Organizations should also consider implementing network segmentation and access controls to limit exposure, while security teams should monitor for any related exploitation attempts in threat intelligence feeds. Additionally, users should be educated about the importance of keeping their cryptographic software updated and the potential risks of connecting to untrusted networks or servers that might not be properly patched.