CVE-2017-10741 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 ntdll_77df0000!RtlpWaitOnCriticalSection+0x0000000000000121."
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Analysis
by VulDB Data Team • 07/01/2020
The vulnerability CVE-2017-10741 affects XnView Classic for Windows version 2.40 and represents a critical security flaw that enables remote code execution or denial of service through maliciously crafted .rle files. This issue stems from improper input validation within the image processing component that handles Run-Length Encoded file formats. The vulnerability manifests when the application attempts to process a specially crafted .rle file that triggers an access violation in the user mode write operation within the ntdll.dll module. The specific error occurs at the RtlpWaitOnCriticalSection function, indicating a race condition or improper synchronization mechanism during memory allocation operations. This type of vulnerability falls under the CWE-121 category of Stack-based Buffer Overflow, where the application fails to properly validate buffer boundaries during image decompression processes. The attack vector leverages the application's failure to sanitize input data from external sources, particularly when processing image files that may contain malformed or oversized data structures that exceed expected memory allocation limits.
The technical exploitation of this vulnerability requires an attacker to craft a malicious .rle file that triggers a specific memory access pattern causing the application to crash or potentially execute arbitrary code. The error message referencing ntdll_77df0000!RtlpWaitOnCriticalSection indicates that the flaw occurs within the Windows kernel's critical section handling mechanism, suggesting that the vulnerability may be related to improper thread synchronization or memory management during file processing operations. This particular memory address and function name point to a low-level Windows subsystem failure that occurs when the application attempts to write to memory locations that are either protected or improperly allocated. The vulnerability can be exploited through social engineering tactics where users are tricked into opening the malicious file, or through automated systems that process untrusted image files. According to ATT&CK framework technique T1203, this vulnerability represents a privilege escalation opportunity through application execution, while T1059 indicates potential command execution capabilities if the flaw allows for code injection.
The operational impact of CVE-2017-10741 extends beyond simple denial of service scenarios to potentially enable full system compromise when exploited by sophisticated attackers. The vulnerability affects any system running XnView Classic 2.40 and could be leveraged in targeted attacks against organizations that rely on this image viewer for document processing or file sharing operations. The flaw demonstrates a fundamental security weakness in the application's input handling mechanisms, where insufficient bounds checking and memory validation allows attackers to manipulate the application's execution flow. When exploited successfully, this vulnerability could allow attackers to execute arbitrary code with the privileges of the user running the application, potentially leading to complete system compromise. The vulnerability also impacts system availability as attackers can cause denial of service by triggering crashes during normal image viewing operations. Organizations using XnView Classic in enterprise environments may face increased risk due to the application's widespread deployment and the difficulty of patching legacy software components. The vulnerability's exploitation requires minimal technical skill, making it particularly dangerous for organizations with less sophisticated security awareness programs.
Mitigation strategies for CVE-2017-10741 should focus on immediate application updates and deployment of security patches provided by the vendor. Organizations should implement strict file validation policies that prevent automatic processing of untrusted image files, particularly those with .rle extensions. Network-level controls such as content filtering and email scanning can help prevent delivery of malicious files to end users. The implementation of application whitelisting policies can restrict execution of vulnerable applications until proper patches are deployed. Security monitoring should include detection of unusual application behavior patterns that may indicate exploitation attempts, particularly around memory access violations and process crashes. System administrators should consider implementing sandboxing techniques for image viewing operations to limit potential damage from successful exploitation attempts. The vulnerability highlights the importance of regular software updates and vulnerability management programs, as the flaw existed in a widely deployed application version that had not received timely security updates. Organizations should also consider migrating to more modern image viewing applications that have better security track records and active maintenance programs. The ATT&CK framework suggests implementing defensive measures such as process injection prevention and memory protection controls to reduce the attack surface and limit exploitation capabilities of this type of vulnerability.