CVE-2017-9878 in IrfanView
Summary
by MITRE
IrfanView version 4.44 (32bit) with FPX Plugin 4.46 allows attackers to execute arbitrary code or cause a denial of service via a crafted .fpx file, related to a "Read Access Violation on Control Flow starting at FPX!FPX_GetScanDevicePropertyGroup+0x000000000000c99a."
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Analysis
by VulDB Data Team • 10/23/2019
The vulnerability CVE-2017-9878 represents a critical security flaw in IrfanView version 4.44 when utilized with the FPX Plugin version 4.46, exposing users to potential arbitrary code execution or denial of service attacks through maliciously crafted .fpx files. This issue manifests as a read access violation occurring at the control flow level within the FPX plugin's FPX_GetScanDevicePropertyGroup function, specifically at the memory address offset 0x000000000000c99a. The flaw demonstrates a classic buffer over-read condition where the application fails to properly validate input data from the FPX file format, leading to unpredictable memory access patterns that can be exploited by malicious actors. The vulnerability operates at the intersection of software exploitation techniques and memory corruption vulnerabilities, making it particularly dangerous in environments where users might encounter untrusted image files.
The technical implementation of this vulnerability stems from improper bounds checking within the FPX plugin's parsing logic for the .fpx file format. When IrfanView processes a crafted FPX file, the FPX_GetScanDevicePropertyGroup function attempts to read memory locations beyond the allocated buffer boundaries, causing a control flow disruption that can be leveraged to redirect execution to attacker-controlled code. This type of vulnerability aligns with CWE-125: "Out-of-bounds Read" and CWE-787: "Out-of-bounds Write" categories, representing a fundamental flaw in input validation and memory management practices. The specific memory access violation occurs during the plugin's initialization phase when it attempts to parse device property groups from the FPX file structure, indicating that the vulnerability exists in the plugin's file format handling rather than the core IrfanView application.
The operational impact of CVE-2017-9878 extends beyond simple denial of service to encompass full system compromise potential through arbitrary code execution. An attacker who successfully exploits this vulnerability could execute malicious code with the privileges of the user running IrfanView, potentially leading to complete system compromise, data exfiltration, or establishment of persistent backdoors. The vulnerability's exploitation requires the victim to open a specially crafted .fpx file, making it susceptible to social engineering attacks where users might unknowingly execute malicious payloads through seemingly legitimate image files. This attack vector aligns with ATT&CK technique T1068: "Exploitation for Privilege Escalation" and T1203: "Exploitation for Client Execution," demonstrating how file format vulnerabilities can serve as initial access vectors in broader attack chains. The vulnerability's impact is particularly severe in enterprise environments where image viewing applications are frequently used and where users might encounter untrusted files through email attachments, web downloads, or file sharing platforms.
Mitigation strategies for CVE-2017-9878 should prioritize immediate software updates and patches from IrfanView's official sources, as the vulnerability was addressed in subsequent releases of both the main application and the FPX plugin. System administrators should implement application whitelisting policies to restrict execution of IrfanView and its plugins to trusted environments, while also deploying network-based intrusion detection systems that can identify suspicious FPX file patterns. Users should be educated about the risks of opening untrusted image files and encouraged to verify file sources before processing. Additional protective measures include implementing sandboxing techniques for image viewing applications, configuring automatic file type validation, and establishing regular software update procedures. Organizations should also consider disabling FPX plugin functionality entirely if the plugin is not required for business operations, as this eliminates the attack surface associated with the vulnerable code. The vulnerability serves as a reminder of the critical importance of proper input validation and memory management in plugin architectures, where third-party components can introduce significant security risks to otherwise secure applications.