CVE-2017-9884 in IrfanView
Summary
by MITRE
IrfanView version 4.44 (32bit) with FPX Plugin 4.46 allows attackers to cause a denial of service or possibly have unspecified other impact via a crafted .fpx file, related to "Data from Faulting Address controls Branch Selection starting at ntdll_77df0000!RtlpCoalesceFreeBlocks+0x00000000000001b6."
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Analysis
by VulDB Data Team • 10/23/2019
The vulnerability identified as CVE-2017-9884 affects IrfanView version 4.44 when used with the FPX Plugin version 4.46, presenting a significant security risk through a carefully crafted .fpx file that can trigger either denial of service or potentially more severe unspecified impacts. This vulnerability manifests within the ntdll.dll module of the Windows operating system, specifically at the RtlpCoalesceFreeBlocks function where faulting address data influences branch selection, creating a predictable exploitation vector. The flaw represents a classic heap-based buffer overflow condition that occurs during the processing of malformed FPX image files, allowing attackers to manipulate memory control flow through crafted input data.
The technical exploitation of this vulnerability occurs when IrfanView processes an attacker-controlled .fpx file through its FPX plugin component, which then invokes the vulnerable ntdll function during memory management operations. The faulting address controls branch selection within the RtlpCoalesceFreeBlocks function, creating a condition where malicious input can cause the application to follow unintended execution paths. This mechanism aligns with CWE-121, heap-based buffer overflow conditions, and demonstrates how improper memory management in image processing plugins can create dangerous attack surfaces. The vulnerability is particularly concerning because it operates at the kernel level through ntdll.dll, making it difficult to contain and potentially exploitable for privilege escalation attacks.
The operational impact of CVE-2017-9884 extends beyond simple denial of service scenarios, as the unspecified other impacts could include arbitrary code execution or system instability. When an attacker successfully exploits this vulnerability, they can potentially cause the target system to crash or become unresponsive, effectively creating a denial of service condition that disrupts normal operations. The vulnerability's location within the Windows kernel functions means that successful exploitation could allow attackers to execute code with the privileges of the affected application, which in this case would be IrfanView running with the privileges of the logged-in user. This scenario aligns with ATT&CK technique T1059.007 for command and scripting interpreter, where the compromised system could be used for further malicious activities.
Mitigation strategies for this vulnerability should focus on immediate patching of IrfanView and the FPX plugin to the latest versions that address the heap management issues. System administrators should implement network segmentation and application whitelisting to prevent unauthorized execution of potentially vulnerable software. Additionally, users should be educated about the risks of opening untrusted image files and the importance of keeping software updated. The vulnerability demonstrates the critical importance of proper input validation in multimedia processing libraries and highlights how seemingly benign file format processing can create severe security implications. Organizations should also consider implementing endpoint protection solutions that can detect and block exploitation attempts targeting known vulnerable functions within Windows system libraries.