CVE-2005-0396 in KDE
Summary
by MITRE
Desktop Communication Protocol (DCOP) daemon, aka dcopserver, in KDE before 3.4 allows local users to cause a denial of service (dcopserver consumption) by "stalling the DCOP authentication process."
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Analysis
by VulDB Data Team • 07/05/2025
The vulnerability identified as CVE-2005-0396 resides within the Desktop Communication Protocol daemon, commonly known as dcopserver, which is a core component of the KDE desktop environment. This daemon serves as the communication layer that enables applications within the KDE ecosystem to interact with each other and with the desktop environment itself. The issue affects KDE versions prior to 3.4, representing a significant security flaw that could be exploited by local attackers to disrupt system operations. The vulnerability specifically targets the authentication mechanism of the DCOP protocol, which is fundamental to how applications establish trusted communication channels within the KDE environment.
The technical flaw manifests when local users manipulate the DCOP authentication process in a manner that causes the dcopserver daemon to become unresponsive or consume excessive system resources. This occurs through what is termed "stalling" the authentication process, where an attacker can submit authentication requests that remain in a pending state indefinitely. The daemon's handling of these stalled connections creates a resource exhaustion condition where system memory and processing power become consumed by the accumulation of these pending authentication attempts. This behavior represents a classic denial of service vulnerability where legitimate system resources are consumed by malicious or malformed requests, preventing the daemon from processing legitimate authentication requests from authorized applications.
The operational impact of this vulnerability extends beyond simple service disruption, as it can affect the entire KDE desktop environment's functionality. When the dcopserver becomes unresponsive due to resource exhaustion, applications that depend on DCOP communication may fail to launch or operate correctly, effectively rendering parts of the desktop environment unusable. This vulnerability is particularly concerning because it requires no special privileges beyond local access, making it exploitable by any user with access to the system. The impact is amplified in multi-user environments where a single malicious user could potentially disrupt desktop services for all users on the system, creating widespread operational disruption that affects productivity and system availability.
Mitigation strategies for this vulnerability involve upgrading to KDE version 3.4 or later, which includes patches addressing the authentication handling flaw in the dcopserver daemon. System administrators should also implement monitoring for unusual resource consumption patterns in the dcopserver process and consider implementing resource limits on authentication processes to prevent complete system exhaustion. From a security perspective, this vulnerability aligns with CWE-400, which describes "Uncontrolled Resource Consumption" as a common weakness in software systems, and can be categorized under ATT&CK technique T1499.004 for "Endpoint Denial of Service" where adversaries consume system resources to deny service to legitimate users. The vulnerability demonstrates the importance of proper resource management in daemon processes and highlights the need for robust input validation and timeout mechanisms in authentication protocols to prevent resource exhaustion attacks.