CVE-2016-9392 in Outside In Technology
Summary
by MITRE
The calcstepsizes function in jpc_dec.c in JasPer before 1.900.17 allows remote attackers to cause a denial of service (assertion failure) via a crafted file.
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Analysis
by VulDB Data Team • 06/28/2023
The vulnerability identified as CVE-2016-9392 resides within the JasPer library version 1.900.16 and earlier, specifically in the calcstepsizes function located in the jpc_dec.c file. This flaw represents a critical denial of service vulnerability that can be exploited by remote attackers through the careful crafting of malicious input files. The issue manifests as an assertion failure during the decoding process, effectively crashing the application and rendering it unavailable to legitimate users. The JasPer library serves as a widely-used open-source implementation for handling JPEG 2000 image format operations, making this vulnerability particularly concerning given the library's extensive deployment across various software applications and systems.
The technical root cause of this vulnerability stems from inadequate input validation within the calcstepsizes function, which is responsible for calculating step sizes during the JPEG 2000 decoding process. When processing malformed or specially crafted input files, the function fails to properly validate the parameters it receives, leading to an assertion failure that terminates the application. This type of vulnerability falls under the CWE-691 category of Insufficient Control Flow Management, where the software fails to properly control the execution flow when encountering unexpected input conditions. The assertion failure occurs because the function does not adequately check boundary conditions or parameter ranges, allowing malicious input to trigger an internal consistency check that was designed to catch programming errors during development rather than handle malformed user input.
The operational impact of CVE-2016-9392 extends beyond simple service disruption, as it can be leveraged by attackers to perform systematic denial of service attacks against systems that rely on JasPer for image processing. Applications that utilize the affected library, including web servers, image processing frameworks, and multimedia applications, become vulnerable to remote exploitation. The vulnerability is particularly dangerous because it requires no special privileges or authentication to exploit, making it accessible to any attacker who can submit crafted files to a vulnerable system. This characteristic aligns with the ATT&CK technique T1499.004, which describes the use of denial of service attacks to disrupt availability of systems and services. The attack surface is broad since JPEG 2000 is used in various contexts including medical imaging systems, satellite imagery processing, and digital photography applications, each potentially serving as an entry point for exploitation.
Mitigation strategies for this vulnerability primarily involve upgrading to JasPer version 1.900.17 or later, which includes proper input validation and error handling in the calcstepsizes function. System administrators should prioritize patching affected systems, particularly those handling user-uploaded content or processing external image files. Additional protective measures include implementing input validation at multiple layers, deploying sandboxing mechanisms for image processing operations, and establishing monitoring for unusual application termination patterns. The fix implemented in version 1.900.17 demonstrates proper defensive programming practices by ensuring that all input parameters are validated before being used in critical calculations, thereby preventing the assertion failure that previously occurred. Organizations should also consider implementing network segmentation and access controls to limit the potential impact of exploitation, while maintaining regular vulnerability assessments to identify other potential attack vectors within their image processing pipelines.