CVE-2020-11049 in FreeRDP
Summary
by MITRE
In FreeRDP after 1.1 and before 2.0.0, there is an out-of-bound read of client memory that is then passed on to the protocol parser. This has been patched in 2.0.0.
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Analysis
by VulDB Data Team • 10/15/2020
The vulnerability identified as CVE-2020-11049 represents a critical out-of-bounds memory read flaw within the FreeRDP remote desktop protocol implementation. This issue affects versions prior to 2.0.0 and specifically impacts the client-side memory handling mechanisms that process incoming protocol data. The flaw manifests when the client application reads memory locations beyond the allocated buffer boundaries, creating a potential vector for information disclosure and system instability.
FreeRDP serves as an open-source implementation of the Remote Desktop Protocol (RDP) that enables remote desktop connections across various operating systems. The vulnerability occurs during the protocol parsing phase where client memory is accessed beyond its intended boundaries. This out-of-bounds read operation can expose sensitive data from adjacent memory locations, potentially including authentication credentials, session tokens, or other confidential information stored in the application's memory space. The flaw is particularly concerning because it occurs before the protocol data is properly validated or sanitized, allowing malicious actors to potentially exploit this weakness during the initial connection establishment phase.
The operational impact of this vulnerability extends beyond simple memory corruption, as it can lead to information disclosure that compromises the security of remote desktop sessions. Attackers could leverage this flaw to extract sensitive data from the client application's memory, potentially enabling further attacks such as credential theft or session hijacking. The vulnerability affects the core protocol handling functionality, meaning any remote desktop connection using affected FreeRDP versions could be at risk. This issue particularly impacts enterprise environments where remote desktop services are extensively used, as it could allow unauthorized access to corporate networks through compromised client endpoints.
From a cybersecurity perspective, this vulnerability aligns with CWE-125, which describes out-of-bounds read conditions in software implementations. The flaw demonstrates a classic memory safety issue that can be exploited through protocol-based attacks, making it relevant to ATT&CK techniques involving credential access and privilege escalation. The patch implemented in FreeRDP version 2.0.0 addresses the memory boundary checking mechanisms to prevent unauthorized memory access. Organizations should prioritize upgrading to the patched version to mitigate this vulnerability, as the out-of-bounds read could potentially be chained with other exploits to achieve more severe impacts. System administrators should also implement monitoring for unusual memory access patterns and consider network segmentation to limit the potential impact of such vulnerabilities in their environments.