CVE-2017-4907 in Unified Access Gateway
Summary
by MITRE
VMware Unified Access Gateway (2.5.x, 2.7.x, 2.8.x prior to 2.8.1) and Horizon View (7.x prior to 7.1.0, 6.x prior to 6.2.4) contain a heap buffer-overflow vulnerability which may allow a remote attacker to execute code on the security gateway.
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Analysis
by VulDB Data Team • 12/26/2020
The vulnerability identified as CVE-2017-4907 represents a critical heap buffer-overflow flaw affecting VMware Unified Access Gateway and Horizon View products. This vulnerability resides in the handling of specific input data structures within the affected software components, creating a potential entry point for remote code execution attacks. The flaw manifests in versions 2.5.x, 2.7.x, and 2.8.x of Unified Access Gateway prior to 2.8.1, as well as various versions of Horizon View including 7.x prior to 7.1.0 and 6.x prior to 6.2.4. The vulnerability stems from inadequate bounds checking during memory allocation and data processing operations, which allows attackers to manipulate heap memory structures through carefully crafted input sequences.
The technical implementation of this vulnerability involves improper memory management practices that create exploitable conditions within the application's heap allocation mechanisms. When the affected software processes specific network requests or data inputs, it fails to validate the size or boundaries of incoming data before copying it into allocated heap buffers. This oversight enables attackers to overflow the intended buffer space and potentially overwrite adjacent memory locations, including function return addresses or critical control data. The vulnerability aligns with CWE-121, which specifically addresses stack buffer overflow conditions, though this instance operates within heap memory contexts. The flaw demonstrates characteristics consistent with memory corruption vulnerabilities that are frequently targeted in exploit development and advanced persistent threat campaigns.
The operational impact of CVE-2017-4907 extends beyond simple privilege escalation or denial of service scenarios, as it provides remote attackers with the capability to execute arbitrary code on affected security gateway systems. This represents a significant risk to organizations relying on these VMware products for network security and access control. Attackers could leverage this vulnerability to gain unauthorized access to protected network resources, potentially compromising entire security infrastructures. The vulnerability's remote exploitability means that attackers do not require physical access or local credentials to initiate attacks, making it particularly dangerous for perimeter security devices. Security gateways that are typically protected by firewalls and network segmentation become vulnerable attack vectors, potentially allowing lateral movement within networks and access to sensitive data repositories.
Organizations affected by this vulnerability should prioritize immediate remediation through official VMware patches and updates. The recommended mitigation strategy involves upgrading to patched versions of Unified Access Gateway 2.8.1 or later, and Horizon View 7.1.0 or 6.2.4 or later. Security teams should implement network segmentation controls and monitoring to detect potential exploitation attempts, particularly focusing on unusual network traffic patterns or malformed requests targeting the affected systems. The vulnerability's classification under ATT&CK technique T1203, which covers Exploitation for Client Execution, indicates that defensive measures should include endpoint detection and response capabilities. Additionally, organizations should conduct comprehensive vulnerability assessments to identify any other potentially affected systems within their infrastructure, as the vulnerability may exist in other VMware products or related components. Network administrators should also consider implementing intrusion detection systems that can identify and block malicious traffic patterns associated with buffer overflow exploitation attempts.