CVE-2014-0791 in FreeRDP
Summary
by MITRE
Integer overflow in the license_read_scope_list function in libfreerdp/core/license.c in FreeRDP through 1.0.2 allows remote RDP servers to cause a denial of service (application crash) or possibly have unspecified other impact via a large ScopeCount value in a Scope List in a Server License Request packet.
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Analysis
by VulDB Data Team • 01/18/2022
The vulnerability identified as CVE-2014-0791 represents a critical integer overflow flaw within the FreeRDP library version 1.0.2 and earlier. This issue resides in the license_read_scope_list function located in the libfreerdp/core/license.c file, which is responsible for processing RDP server license requests. The flaw occurs when a remote RDP server sends a maliciously crafted Server License Request packet containing an oversized ScopeCount value within the Scope List field, creating a condition where integer arithmetic operations exceed the maximum representable value for the data type used in the implementation.
The technical exploitation of this vulnerability demonstrates a classic integer overflow scenario that falls under the CWE-190 category of Integer Overflow or Wraparound. When the ScopeCount value exceeds the maximum value that can be stored in the designated integer variable, the arithmetic operation wraps around to a much smaller value, leading to improper memory allocation or buffer handling within the license processing routine. This behavior creates a potential for memory corruption that can result in application instability and system crashes. The vulnerability's impact extends beyond simple denial of service, as the unspecified other impacts could potentially include arbitrary code execution or privilege escalation depending on the execution context and memory layout.
From an operational perspective, this vulnerability presents a significant risk to organizations relying on FreeRDP implementations for remote desktop connections, particularly in enterprise environments where RDP services are extensively used. The remote nature of the attack means that malicious actors can exploit this flaw without requiring local access to the target system, making it particularly dangerous in networked environments. The vulnerability affects the core licensing functionality of the RDP protocol implementation, which is fundamental to establishing secure remote desktop connections, potentially allowing attackers to disrupt legitimate remote access services or create opportunities for more sophisticated attacks.
The mitigation strategies for CVE-2014-0791 primarily involve immediate patching of FreeRDP installations to versions that contain the necessary fixes for the integer overflow condition. Organizations should prioritize updating their FreeRDP implementations to versions 1.0.3 or later, which include proper input validation and bounds checking for the ScopeCount parameter. Network administrators should also implement monitoring and intrusion detection systems to identify potential exploitation attempts through anomalous RDP traffic patterns. Additionally, implementing network segmentation and access controls to limit RDP server access can reduce the attack surface and prevent unauthorized entities from reaching vulnerable FreeRDP implementations. The vulnerability aligns with ATT&CK technique T1210 for exploitation of remote services and represents a common class of vulnerabilities that can be addressed through proper input validation and defensive programming practices.