CVE-2017-2155 in Viewer
Summary
by MITRE
Buffer overflow in Hoozin Viewer 2, 3, 4.1.5.15 and earlier, 5.1.2.13 and earlier, and 6.0.3.09 and earlier allows remote attackers to execute arbitrary code via specially crafted webpage.
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Analysis
by VulDB Data Team • 09/22/2020
The vulnerability identified as CVE-2017-2155 represents a critical buffer overflow flaw within multiple versions of Hoozin Viewer software across its 2.x, 5.x, and 6.x release lines. This vulnerability exists in the web page rendering engine of the viewer application, specifically affecting versions up to 4.1.5.15, 5.1.2.13, and 6.0.3.09. The flaw stems from insufficient input validation and memory management within the application's handling of specially crafted web content, creating a condition where attacker-controlled data can overflow allocated buffer space and overwrite adjacent memory locations.
The technical implementation of this vulnerability involves a classic buffer overflow scenario where the Hoozin Viewer application fails to properly bounds-check user-supplied data when processing web content. When a remote attacker constructs a malicious webpage containing oversized or malformed data structures, the application's memory allocation routines become compromised. This overflow can overwrite critical program memory including return addresses, function pointers, and other control data structures, enabling attackers to manipulate the program execution flow. The vulnerability is classified under CWE-121 as a stack-based buffer overflow, which directly enables arbitrary code execution capabilities.
From an operational standpoint, this vulnerability presents a severe risk to organizations deploying Hoozin Viewer software, particularly in environments where users may encounter untrusted web content. Attackers can leverage this flaw by hosting malicious web pages that, when loaded through the vulnerable viewer application, trigger the buffer overflow condition. The remote exploitation capability means that no local access is required, making the attack surface particularly broad. Successful exploitation results in complete system compromise, allowing attackers to execute arbitrary code with the privileges of the affected application user, potentially leading to full system takeover or data exfiltration.
The impact of this vulnerability extends beyond immediate exploitation as it represents a persistent threat vector that can be maintained through various attack delivery mechanisms. Organizations using affected versions should consider the potential for persistent backdoors or additional compromise through secondary attacks once initial access is achieved. The vulnerability's presence in multiple release lines indicates a fundamental flaw in the application's memory management that requires immediate remediation. Security practitioners should implement network-based mitigations including web content filtering and application whitelisting to prevent exploitation until proper patches are deployed. This vulnerability aligns with ATT&CK technique T1203 (Exploitation for Client Execution) and demonstrates the importance of maintaining up-to-date software components to prevent known vulnerabilities from being exploited in enterprise environments.