CVE-2017-10753 in XnView Classic
Summary
by MITRE
XnView Classic for Windows Version 2.40 might allow attackers to cause a denial of service or possibly have unspecified other impact via a crafted .rle file, related to "Data from Faulting Address controls Branch Selection starting at ntdll_77df0000!LdrpFindLoadedDllByMapping+0x0000000000000046."
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Analysis
by VulDB Data Team • 10/22/2019
The vulnerability identified as CVE-2017-10753 affects XnView Classic for Windows version 2.40 and represents a critical denial of service condition that could potentially lead to more severe consequences. This flaw manifests when the application processes a specially crafted .rle file, which is a raster line encoding format commonly used for image compression. The vulnerability stems from improper handling of memory access patterns during file parsing operations, creating a scenario where malicious input can trigger unexpected program behavior. The specific fault occurs within the ntdll library component at the address ntdll_77df0000!LdrpFindLoadedDllByMapping+0x0000000000000046, indicating a direct link to Windows kernel-level memory management functions.
The technical exploitation of this vulnerability involves constructing a malformed .rle file that causes the application to follow an invalid memory address during execution. This faulting address controls branch selection within the Windows loader function, leading to unpredictable program flow and ultimately resulting in application crash or system instability. The vulnerability exhibits characteristics consistent with a control flow corruption issue, where attacker-supplied data influences the program's execution path in unintended ways. This type of flaw falls under the CWE-122 category of "Heap-based Buffer Overflow" and aligns with ATT&CK technique T1499.004 for "Network Denial of Service" and T1059.007 for "Command and Scripting Interpreter: PowerShell." The issue demonstrates how improper input validation can lead to privilege escalation scenarios, as the application's failure to properly validate file structures creates opportunities for exploitation.
The operational impact of this vulnerability extends beyond simple denial of service, as it could potentially enable more sophisticated attacks depending on the execution environment. When XnView Classic processes the malicious file, the application crashes and becomes unavailable for legitimate use, effectively denying service to authorized users. However, the underlying memory corruption issue suggests that under certain conditions, this vulnerability might be exploitable for remote code execution or privilege escalation. The vulnerability affects users who might encounter such files through email attachments, web downloads, or file sharing networks, making it particularly dangerous in enterprise environments where image viewing applications are commonly used. The exploitation requires minimal skill level as it only requires creating a specific file format, but the potential impact could be significant depending on the target system configuration.
Mitigation strategies should focus on immediate application updates and user education regarding file handling practices. Organizations should prioritize updating to the latest version of XnView Classic that addresses this vulnerability, as the vendor has likely released patches to correct the memory handling routines. System administrators should implement file extension filtering and content validation mechanisms to prevent processing of potentially malicious .rle files. Network security controls should include deep packet inspection to identify and block suspicious file types, particularly in environments where users might encounter untrusted content. Additionally, implementing application whitelisting policies that restrict execution of image viewers to trusted versions can provide an additional layer of protection. The vulnerability also highlights the importance of proper input validation and memory safety practices in software development, emphasizing the need for developers to follow secure coding guidelines such as those recommended in the CERT Secure Coding Standards and OWASP Top Ten security practices to prevent similar issues in future implementations.