CVE-2013-4118 in FreeRDP
Summary
by MITRE
FreeRDP before 1.1.0-beta1 allows remote attackers to cause a denial of service (NULL pointer dereference and application crash) via unspecified vectors.
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Analysis
by VulDB Data Team • 09/21/2022
The vulnerability identified as CVE-2013-4118 affects FreeRDP versions prior to 1.1.0-beta1, representing a critical denial of service flaw that can be exploited by remote attackers to crash the application. This vulnerability manifests through a NULL pointer dereference condition that occurs when the remote desktop protocol implementation processes certain malformed or unexpected input data. The flaw exists within the FreeRDP library that provides remote desktop connectivity functionality for various operating systems and applications. Attackers can leverage this vulnerability by sending specially crafted packets or connection requests to a vulnerable FreeRDP implementation, triggering the application to attempt to access a NULL memory pointer which results in an immediate crash and subsequent denial of service condition.
The technical nature of this vulnerability places it squarely within the category of memory safety issues, specifically relating to improper handling of null pointers during memory access operations. According to CWE classification, this corresponds to CWE-476 which describes NULL Pointer Dereference, a common weakness that occurs when an application attempts to access memory through a pointer that has not been properly initialized or has been set to NULL. The vulnerability demonstrates a classic flaw in input validation and error handling within the remote desktop protocol stack where the system fails to properly validate incoming connection data or handshake parameters before attempting to process them. This type of vulnerability is particularly dangerous in network services as it can be exploited without authentication and can be easily automated to cause widespread disruption.
The operational impact of CVE-2013-4118 extends beyond simple service disruption, as it can affect any system running vulnerable FreeRDP implementations including servers, desktop applications, and mobile platforms that utilize the library for remote desktop connectivity. Organizations using FreeRDP for remote access services, virtual desktop infrastructure, or remote administration tasks face significant risk of service interruption when this vulnerability is exploited. The remote exploit nature means that attackers do not require physical access or local privileges to cause the disruption, making it particularly concerning for enterprise environments where remote desktop services are commonly deployed. Additionally, the vulnerability can be leveraged as part of larger attack campaigns where initial access is gained through other means, followed by service disruption to hinder incident response or maintain persistence.
Mitigation strategies for this vulnerability primarily focus on immediate patching of affected FreeRDP installations to version 1.1.0-beta1 or later, which contains the necessary code fixes to properly handle null pointer conditions during remote desktop protocol processing. System administrators should prioritize updating all instances of FreeRDP across their infrastructure, particularly those serving remote desktop services or acting as RDP gateways. Network segmentation and access controls should be implemented to limit exposure of vulnerable systems to untrusted networks, while monitoring should be enabled to detect potential exploitation attempts. From an ATT&CK framework perspective, this vulnerability aligns with techniques involving service stoppage and denial of service operations, and may be used as part of initial access or lateral movement phases where attackers seek to disrupt services and create confusion during incident response activities. Organizations should also implement proper input validation and error handling procedures in their own applications that utilize FreeRDP to prevent similar issues from propagating through their own codebases.