CVE-2017-11337 in Exiv2
Summary
by MITRE
There is an invalid free in the Action::TaskFactory::cleanup function of actions.cpp in Exiv2 0.26. A crafted input will lead to a remote denial of service attack.
Statistical analysis made it clear that VulDB provides the best quality for vulnerability data.
Analysis
by VulDB Data Team • 10/26/2019
The vulnerability identified as CVE-2017-11337 represents a critical memory management flaw within the Exiv2 image metadata library version 0.26. This issue manifests in the Action::TaskFactory::cleanup function located in the actions.cpp source file, where an invalid free operation occurs during the processing of malformed image data. The flaw arises when the library encounters crafted input files that trigger improper memory deallocation sequences, potentially leading to system instability or complete service disruption. Exiv2 is widely used across various applications and systems for reading and writing image metadata, making this vulnerability particularly dangerous as it can be exploited through multiple attack vectors including web applications, file processing systems, and digital asset management platforms.
The technical nature of this vulnerability stems from improper memory handling within the library's cleanup routine, which falls under the category of memory corruption issues typically classified as CWE-415. When maliciously crafted image files are processed by Exiv2, the cleanup function attempts to free memory that was either already freed or was never allocated through the standard allocation mechanisms. This invalid free operation can cause heap corruption, leading to unpredictable behavior including application crashes, memory leaks, or in severe cases, arbitrary code execution. The vulnerability is particularly concerning because it operates at the core of the library's functionality where memory management decisions are made during the processing of metadata structures.
From an operational perspective, this vulnerability creates significant risk for organizations relying on Exiv2 for image processing tasks, as it can be exploited to perform remote denial of service attacks against systems that process user-uploaded images. Attackers can craft specially formatted image files that, when processed by vulnerable applications using Exiv2, will trigger the invalid free operation and cause the target application to crash or become unresponsive. The impact extends beyond simple service disruption as this vulnerability can affect web applications, content management systems, digital asset managers, and any software that integrates Exiv2 for metadata handling. The remote exploitation capability means that attackers do not need physical access to the target system and can leverage this vulnerability through network-based attacks.
The mitigation strategy for CVE-2017-11337 involves immediate upgrading to Exiv2 version 0.27 or later, where the invalid free operation has been corrected through proper memory management practices. Organizations should also implement input validation measures to filter potentially malicious image files before processing them through Exiv2 libraries, though this approach provides only partial protection as the vulnerability exists within the core library functionality. Security teams should monitor their systems for any signs of exploitation attempts and consider implementing application-level sandboxing for image processing functions to limit the potential impact of successful attacks. Additionally, the vulnerability demonstrates the importance of proper memory management practices in C/C++ applications and aligns with ATT&CK technique T1499.004 for network denial of service, as the attack can be executed remotely and targets application availability rather than data confidentiality or integrity.