CVE-2017-6313 in gdk-pixbuf
Summary
by MITRE
Integer underflow in the load_resources function in io-icns.c in gdk-pixbuf allows context-dependent attackers to cause a denial of service (out-of-bounds read and program crash) via a crafted image entry size in an ICO file.
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Analysis
by VulDB Data Team • 09/05/2020
The vulnerability identified as CVE-2017-6313 represents a critical integer underflow flaw within the gdk-pixbuf library's handling of ICO file formats. This issue specifically affects the load_resources function in the io-icns.c file, which processes image entry sizes during ICO file parsing operations. The vulnerability stems from inadequate input validation mechanisms that fail to properly handle malformed integer values, creating a scenario where arithmetic operations can produce unexpectedly small results that fall below the expected minimum bounds.
The technical implementation of this vulnerability manifests when an attacker crafts a malicious ICO file containing manipulated image entry size values that trigger integer underflow conditions. When the load_resources function processes these malformed entries, it performs arithmetic operations that result in negative or unexpectedly small integer values. These invalid values subsequently propagate through the code execution path and lead to out-of-bounds memory read operations, where the application attempts to access memory locations that fall outside the allocated buffer boundaries. This improper memory access pattern directly results in program crashes and system instability.
From an operational perspective, this vulnerability presents significant risk to systems that process untrusted image content, particularly those running applications built on the gdk-pixbuf library such as web browsers, image viewers, and desktop environments. The denial of service impact extends beyond simple application crashes to potentially enable more sophisticated attack vectors if exploited in conjunction with other vulnerabilities. The context-dependent nature of this flaw means that exploitation requires specific conditions involving crafted ICO files, making it less likely to occur in casual browsing scenarios but still posing serious threats to applications that handle file uploads or automated image processing workflows.
The vulnerability aligns with CWE-191, which specifically addresses integer underflow conditions, and demonstrates characteristics consistent with ATT&CK technique T1059.007 for command and scripting interpreter usage in exploitation contexts. Organizations utilizing gdk-pixbuf components should prioritize immediate patching of affected versions, implement strict file format validation procedures, and deploy network-based intrusion detection systems to monitor for suspicious ICO file patterns. Additionally, application developers should consider implementing robust input sanitization mechanisms and memory protection features such as stack canaries and address space layout randomization to mitigate potential exploitation scenarios. The remediation process should include comprehensive testing of image processing workflows and regular security audits of third-party libraries to prevent similar vulnerabilities from emerging in future code releases.
This vulnerability highlights the critical importance of proper integer arithmetic validation in multimedia processing libraries and demonstrates how seemingly minor input validation gaps can result in significant security implications. The impact extends to various operating systems and applications that rely on the gdk-pixbuf library for image handling, making it a widespread concern across multiple software ecosystems and potentially affecting both enterprise and consumer applications that process image content from untrusted sources.