CVE-2016-9398 in Jasper
Summary
by MITRE
The jpc_floorlog2 function in jpc_math.c in JasPer before 1.900.17 allows remote attackers to cause a denial of service (assertion failure) via unspecified vectors.
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Analysis
by VulDB Data Team • 11/14/2022
The vulnerability identified as CVE-2016-9398 represents a critical denial of service flaw within the JasPer image processing library, specifically affecting versions prior to 1.900.17. This issue resides in the jpc_floorlog2 function located within the jpc_math.c source file, which is a core component of the library responsible for handling JPEG 2000 image format processing. The vulnerability manifests when the library encounters malformed or specially crafted input data during the mathematical operations required for image decompression and processing, leading to an assertion failure that terminates the application process.
The technical nature of this vulnerability stems from insufficient input validation and error handling within the mathematical computation function. When the jpc_floorlog2 function processes certain edge cases or invalid numerical inputs, it fails to properly validate the input parameters before performing logarithmic calculations. This weakness creates an environment where an attacker can craft malicious JPEG 2000 files that, when processed by vulnerable JasPer implementations, trigger an assertion failure. The assertion failure occurs because the function expects certain mathematical properties to hold true, but receives inputs that violate these assumptions, causing the program to terminate abruptly rather than gracefully handling the error condition. This behavior aligns with CWE-617, which describes reachable assertions that can be triggered by external input, and represents a classic example of improper error handling that leads to denial of service conditions.
The operational impact of CVE-2016-9398 extends beyond simple service disruption, as it can affect any system or application that relies on JasPer for image processing, including web servers, image handling applications, and multimedia processing systems. Attackers can exploit this vulnerability remotely by uploading or transmitting specially crafted JPEG 2000 files to systems that utilize vulnerable JasPer versions, resulting in application crashes and potential system instability. The vulnerability is particularly concerning in web environments where users can upload images, as it allows for easy exploitation through crafted file uploads that can bring down web applications or entire servers. From an adversary perspective, this vulnerability maps to ATT&CK technique T1499.004, which covers network denial of service attacks, and T1595.001, related to reconnaissance for vulnerabilities in network infrastructure, as attackers can identify and exploit systems using vulnerable image processing libraries. The impact is significant because it affects the availability of services and can be executed with minimal technical expertise, making it a preferred target for attackers seeking to disrupt operations.
Mitigation strategies for CVE-2016-9398 primarily focus on immediate version updates to JasPer 1.900.17 or later, which contain the necessary patches to address the assertion failure in the jpc_floorlog2 function. Organizations should conduct comprehensive vulnerability assessments to identify all systems running vulnerable JasPer versions and prioritize their patching efforts accordingly. Additional defensive measures include implementing input validation controls at application boundaries, where JPEG 2000 files are processed, and deploying intrusion detection systems that can identify suspicious file upload patterns. Network-level mitigations such as content filtering and sandboxing of image processing operations can provide additional layers of protection. System administrators should also consider implementing monitoring and alerting mechanisms to detect application crashes or abnormal termination patterns that may indicate exploitation attempts. The vulnerability serves as a reminder of the importance of proper error handling in mathematical computation functions and the need for robust input validation in security-critical libraries, particularly those handling multimedia file formats that are widely used across internet-facing applications.