CVE-2017-9875 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 "User Mode Write AV starting at FPX!DE_Decode+0x0000000000000cdb."
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Analysis
by VulDB Data Team • 10/23/2019
The vulnerability identified as CVE-2017-9875 affects IrfanView version 4.44 when used with the FPX Plugin version 4.46, representing a critical security flaw that enables remote code execution or denial of service attacks through maliciously crafted .fpx files. This vulnerability manifests as a user mode write access violation within the FPX plugin's decoding function, specifically at the address FPX!DE_Decode+0x0000000000000cdb, indicating a memory corruption issue that occurs during the processing of malformed image data. The flaw exists in the handling of FPX (FlashPix) image format files, which are used for high-resolution imaging and are supported by IrfanView through third-party plugins.
The technical exploitation of this vulnerability occurs when a user opens a specially crafted .fpx file that contains malformed data structures or buffer overflows within the plugin's decoding routine. The access violation at the specified memory address suggests that the plugin attempts to write to an invalid memory location during the decompression or parsing of the FlashPix file format, potentially leading to stack corruption or heap corruption depending on the exact nature of the buffer overflow. This type of vulnerability falls under the CWE-121 category of "Stack-based Buffer Overflow" or potentially CWE-122 for heap-based buffer overflows, as the plugin fails to properly validate input data before processing it.
The operational impact of this vulnerability is severe as it allows attackers to execute arbitrary code on systems running vulnerable versions of IrfanView with the FPX plugin installed. An attacker could craft a malicious .fpx file that, when opened by an unsuspecting user, would trigger the buffer overflow condition and potentially allow remote code execution with the privileges of the user running IrfanView. The denial of service aspect of this vulnerability means that even if code execution cannot be achieved, the application will crash or become unresponsive when processing the malicious file, effectively disrupting legitimate user activities and potentially enabling a denial of service attack against specific targets.
This vulnerability aligns with ATT&CK technique T1203 - Exploitation for Client Execution, where adversaries leverage software vulnerabilities to execute malicious code on target systems. The attack surface is particularly concerning as IrfanView is widely used for image viewing and processing, making it a common target for social engineering attacks where users might inadvertently open malicious files. The vulnerability also demonstrates poor input validation practices that are characteristic of insecure coding patterns, with the plugin failing to implement proper bounds checking and memory management when processing external file formats. Organizations should implement immediate mitigations including disabling the FPX plugin or updating to patched versions of IrfanView, while also considering network-based protections such as email filtering to prevent delivery of malicious .fpx files to end users. The vulnerability highlights the importance of third-party plugin security and the need for comprehensive security testing of all components within image processing software stacks.