CVE-2017-10748 in XnView Classic
Summary
by MITRE
XnView Classic for Windows Version 2.40 allows attackers to execute arbitrary code or cause a denial of service via a crafted .rle file, related to a "User Mode Write AV starting at xnview+0x000000000022bf8d."
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Analysis
by VulDB Data Team • 12/09/2022
CVE-2017-10748 represents a critical vulnerability in XnView Classic for Windows version 2.40 that exposes users to potential arbitrary code execution or denial of service attacks through maliciously crafted .rle files. This vulnerability manifests as a user mode write access violation within the xnview executable, specifically occurring at the memory address xnview+0x000000000022bf8d. The flaw stems from inadequate input validation and memory management during the processing of RLE (Run-Length Encoded) image files, which are commonly used for compressing bitmap images in various applications. When a maliciously constructed .rle file is opened, the application fails to properly validate the file structure and boundaries, leading to memory corruption that can be exploited by attackers to execute arbitrary code within the context of the running application. This vulnerability directly maps to CWE-121, which describes heap-based buffer overflow conditions where insufficient boundary checking allows attackers to overwrite adjacent memory locations. The attack vector is particularly concerning because it requires no special privileges beyond normal user access, making it an attractive target for social engineering campaigns where users might unknowingly open malicious files. The denial of service aspect of this vulnerability occurs when the memory corruption causes the application to crash or become unresponsive, effectively preventing legitimate users from accessing the software. According to ATT&CK framework, this vulnerability aligns with T1203, which covers "Exploitation for Client Execution" and T1499, addressing "Endpoint Denial of Service" through the manipulation of application memory structures. The technical impact is significant as it can be leveraged for privilege escalation attacks, especially when XnView is run with elevated privileges, or to establish persistent access through the execution of malicious payloads. The vulnerability demonstrates poor defensive programming practices and highlights the critical importance of input sanitization in multimedia processing libraries. Organizations should prioritize patching this vulnerability immediately, as it represents a well-documented exploit that can be easily weaponized by threat actors. The memory corruption pattern suggests that the application does not properly implement bounds checking during decompression of RLE data structures, allowing attackers to overwrite critical memory regions including return addresses or function pointers that control program execution flow. This type of vulnerability is particularly dangerous in enterprise environments where image processing applications are frequently used, as it can serve as an initial compromise vector for more extensive attacks. The exploitability of this vulnerability is further enhanced by the fact that RLE files are commonly encountered in email attachments, file sharing systems, and web downloads, making it a prime target for widespread exploitation campaigns. Security professionals should implement network-based detection measures to identify potential exploitation attempts and ensure that all instances of XnView Classic are updated to versions that address this memory corruption vulnerability. The remediation process requires careful application of memory safety controls including stack canaries, address space layout randomization, and improved input validation mechanisms that prevent buffer overflows during image file processing operations.