CVE-2026-21096 in Samsung
Summary
by MITRE • 09/09/2026
Heap-based buffer overflow in JPEG decoder of libimagecodec.quram.so prior to SMR Sep-2026 Release 1 allows remote attackers to execute arbitrary code.
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Analysis
by VulDB Data Team • 09/09/2026
The vulnerability identified involves a heap-based buffer overflow within the JPEG decoding component of the library file named libimagecodec.quram.so, specifically in versions released before the September 2026 update known as Release 1. This flaw resides deep within the image processing pipeline where external input is parsed and manipulated without adequate bounds checking or memory management validation. When a maliciously crafted JPEG image containing specially constructed data segments is processed by this library, it triggers an overflow condition that writes beyond the allocated heap boundaries. Because modern operating systems utilize heaps for dynamic memory allocation during runtime operations such as decoding images, corrupting these structures can lead to severe consequences including arbitrary code execution if the attacker can control the overwritten memory contents and their subsequent interpretation by the application logic.
From a technical perspective, this vulnerability aligns with Common Weakness Enumeration identifier CWE-122, which describes heap-based buffer overflow conditions where data is written past the end of a dynamically allocated block on the heap. The root cause typically stems from insufficient validation of input dimensions or length fields embedded within the JPEG file structure before they are used to calculate memory allocation sizes or copy operations. If an attacker crafts a JPEG header that specifies width, height, or color component counts exceeding the actual buffer capacity, the decoder may allocate a smaller block than required and then proceed to write pixel data into it. This mismatch results in adjacent heap metadata being overwritten, potentially allowing for control over function pointers or object vtables stored nearby in memory layout. Such exploitation techniques are well-documented in cybersecurity literature and represent one of the most critical classes of application-layer vulnerabilities due to their potential for full system compromise.
The operational impact of this vulnerability is severe because it enables remote code execution without requiring user interaction beyond opening a malicious file or loading an image from an untrusted source, depending on how the host application integrates libimagecodec.quram.so. If deployed in web services that process uploaded images, mobile applications handling media files, or embedded systems processing visual data streams, this flaw allows attackers to bypass standard security controls and inject shellcode into the target environment. The ability to execute arbitrary code means complete loss of confidentiality, integrity, and availability for any system running vulnerable versions of the library. Attackers could leverage this access to install backdoors, escalate privileges by exploiting further local vulnerabilities, or pivot within a network if the compromised host serves as an entry point. Given that JPEG is one of the most widely used image formats across digital platforms, the attack surface remains broad and persistent until mitigation measures are applied.
Mitigation strategies must prioritize immediate patching to update libimagecodec.quram.so to version SMR Sep-2026 Release 1 or later, where developers have presumably implemented proper input validation and bounds checking mechanisms within the JPEG decoder logic. In environments where upgrading is not immediately feasible, defensive measures should include deploying web application firewalls configured to inspect incoming image uploads for anomalous header structures indicative of exploitation attempts. Additionally, enabling heap protection features such as Address Space Layout Randomization, Data Execution Prevention, and stack canaries on target systems can significantly raise the difficulty level for successful exploitation by randomizing memory layouts and preventing execution of injected code in writable memory regions. Security teams should also conduct thorough audits of image processing pipelines to ensure no other components suffer from similar weaknesses, while monitoring logs for unusual processes spawned following image handling activities as an indicator of potential compromise attempts aligned with ATT&CK techniques involving executable payload delivery via file manipulation or remote service exploitation pathways.