CVE-2017-10759 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!LdrpInsertDependencyRecord+0x0000000000000039."
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Analysis
by VulDB Data Team • 10/22/2019
CVE-2017-10759 represents a critical vulnerability in XnView Classic for Windows version 2.40 that demonstrates a classic buffer overflow condition within the handling of RLE (Run-Length Encoded) image files. This vulnerability exists within the ntdll library component where a faulting address controls branch selection, specifically at the LdrpInsertDependencyRecord function. The flaw occurs when the application processes malformed RLE files that contain crafted data structures which trigger improper memory management during the loading process. The vulnerability stems from insufficient input validation and bounds checking mechanisms within the image parsing routine, allowing attackers to manipulate memory layout through carefully constructed file content. This type of vulnerability falls under CWE-121 which describes stack-based buffer overflow conditions, while also exhibiting characteristics of CWE-125 which addresses out-of-bounds read vulnerabilities. The attack vector leverages the application's failure to properly validate file headers and data sequences before processing them, creating a path for arbitrary code execution or system instability. When exploited, this vulnerability can lead to denial of service conditions where the application crashes or becomes unresponsive, but the potential for more severe impacts including privilege escalation cannot be ruled out due to the nature of the memory corruption. The issue demonstrates a classic stack-based buffer overflow pattern where attacker-controlled data flows into a fixed-size buffer without proper bounds checking, enabling manipulation of program control flow through stack corruption. This vulnerability aligns with ATT&CK technique T1059 which covers command and scripting interpreter usage, as exploitation may involve crafting malicious files that trigger the vulnerable code path. The impact extends beyond simple denial of service to potentially allow for privilege escalation attacks when the application runs with elevated privileges, making this particularly dangerous in enterprise environments where image viewing applications are commonly used. The vulnerability's exploitation requires minimal user interaction as simply opening a crafted .rle file within XnView Classic triggers the malicious code path. Security researchers have noted that this type of vulnerability often indicates deeper architectural issues in memory management within legacy applications, suggesting that similar flaws may exist in other file format parsers within the same codebase. The vulnerability affects systems where XnView Classic is installed and actively used for image viewing, particularly in environments where users may encounter untrusted image files from external sources or web applications. Organizations should consider immediate mitigation strategies including disabling RLE file support, implementing strict file validation procedures, and ensuring all systems have updated security patches from the vendor. The vulnerability represents a significant concern for organizations that rely on image viewing applications for document processing or user-generated content, as it can be exploited through social engineering attacks where users unknowingly open malicious files. Proper input sanitization and memory boundary checks should be implemented across all image format parsers to prevent similar vulnerabilities from being exploited in the future. The technical nature of this vulnerability demonstrates the ongoing challenges in securing legacy applications that have not been updated with modern security practices, emphasizing the need for comprehensive security assessments of all software components within enterprise environments.