CVE-2017-14552 in STDU Viewer
Summary
by MITRE
STDU Viewer 1.6.375 allows attackers to execute arbitrary code or cause a denial of service via a crafted .djvu file, related to a "User Mode Write AV starting at STDUDjVuFile!DllUnregisterServer+0x000000000000d9a9."
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Analysis
by VulDB Data Team • 11/17/2019
The vulnerability CVE-2017-14552 affects STDU Viewer version 1.6.375, a document viewing application that processes djvu files. This issue represents a critical memory corruption flaw that can be exploited to achieve remote code execution or denial of service conditions. The vulnerability manifests through improper handling of maliciously crafted .djvu files during the file processing lifecycle, specifically within the STDUDjVuFile.dll component that handles djvu file operations.
The technical root cause of this vulnerability stems from a user mode write access violation occurring at the DllUnregisterServer function within the STDUDjVuFile.dll module. This particular memory access violation occurs at offset 0x000000000000d9a9, indicating a classic buffer overflow or memory corruption scenario where attacker-controlled data is processed without proper bounds checking. The vulnerability arises from insufficient input validation when parsing djvu file structures, allowing attackers to craft malicious file content that triggers the memory corruption during file registration or processing operations.
From an operational perspective, this vulnerability presents significant risk to organizations relying on STDU Viewer for document processing. Attackers can exploit this flaw by delivering a specially crafted .djvu file that, when opened or processed by the vulnerable application, triggers the memory corruption. The potential impact includes arbitrary code execution with the privileges of the affected user, complete system compromise, or denial of service conditions that disrupt legitimate document processing workflows. This vulnerability is particularly dangerous because it can be triggered through simple file opening operations without requiring special user interaction beyond the initial file access.
The vulnerability aligns with CWE-121, which describes stack-based buffer overflow conditions, and represents a classic example of how improper input validation can lead to memory corruption exploits. From an attack framework perspective, this vulnerability maps to multiple ATT&CK techniques including execution through file operations, privilege escalation, and denial of service. The exploitation pathway typically involves crafting a malicious djvu file that, when processed by the vulnerable application, causes memory corruption leading to code execution. Organizations should prioritize patching this vulnerability as it represents a high-severity threat that can be exploited remotely without user interaction.
Mitigation strategies include immediate deployment of vendor patches or updates to STDU Viewer, implementing application whitelisting controls to restrict execution of vulnerable applications, and deploying network-based protections such as intrusion detection systems that can detect exploitation attempts. Additionally, organizations should consider implementing sandboxing techniques for document processing operations and conducting regular security assessments to identify similar vulnerabilities in other document processing applications. The vulnerability highlights the importance of proper input validation and memory management practices in document processing software, particularly when handling potentially malicious file formats.