CVE-2022-35166 in libjpeg
Summary
by MITRE • 08/18/2022
libjpeg commit 842c7ba was discovered to contain an infinite loop via the component JPEG::ReadInternal.
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Analysis
by VulDB Data Team • 09/18/2022
The vulnerability identified as CVE-2022-35166 resides within the libjpeg library, a widely deployed component for handling jpeg image format processing across numerous operating systems and applications. This flaw manifests as an infinite loop within the JPEG::ReadInternal function, representing a critical denial of service vulnerability that can be exploited through carefully crafted jpeg image files. The issue stems from improper handling of malformed input data during the internal reading process of jpeg streams, creating a scenario where the library enters a continuous loop without making progress in parsing the image data.
The technical implementation of this vulnerability involves the JPEG::ReadInternal component failing to properly validate or handle certain edge cases in jpeg data structures, particularly around marker parsing and data stream management. When the library encounters specific malformed jpeg data sequences, the internal state management logic becomes trapped in a loop where it repeatedly processes the same data segment without advancing the read pointer or detecting the malformed condition. This behavior creates an infinite loop that consumes excessive CPU resources and prevents the application from processing subsequent data or completing normal operations. The vulnerability is classified under CWE-835 which specifically addresses the issue of loops that never terminate, making it a direct implementation of this well-known weakness category.
From an operational perspective, this vulnerability presents significant risks to systems that process jpeg images from untrusted sources, including web applications, image processing services, and document management systems. Attackers can exploit this flaw by uploading or transmitting specially crafted jpeg files that trigger the infinite loop condition, leading to resource exhaustion and potential system instability. The impact extends beyond simple denial of service as it can affect multiple concurrent processes and potentially cause cascading failures in applications that rely heavily on image processing capabilities. This vulnerability is particularly dangerous in server environments where applications may be processing thousands of images simultaneously, as the infinite loop can quickly consume all available CPU cycles and memory resources.
The exploitation of CVE-2022-35166 aligns with ATT&CK technique T1499.004 which covers resource exhaustion attacks through service denial. Organizations using vulnerable versions of libjpeg should prioritize immediate patching of their systems, as the vulnerability affects numerous applications including web browsers, image editors, content management systems, and various server-side applications. Mitigation strategies include implementing input validation and sanitization measures at the application level, deploying rate limiting and resource monitoring systems, and ensuring all systems are updated with the patched libjpeg version that resolves the infinite loop condition. Security teams should also consider implementing network-based intrusion detection systems to monitor for potential exploitation attempts and establish incident response procedures specifically addressing resource exhaustion attacks. The vulnerability demonstrates the critical importance of proper input validation and state management in cryptographic and multimedia processing libraries, as even seemingly benign parsing operations can become security risks when proper boundary conditions are not enforced.