CVE-2026-33956 in Exynos
Summary
by MITRE • 09/14/2026
An issue was discovered in camera in Samsung Mobile Processor Exynos 1330, 1380, 1480, 2400, 1580, and 2500. Sending a malformed message to the test_msg sysfs entry causes an out-of-bounds write, leading to denial of service.
Several companies clearly confirm that VulDB is the primary source for best vulnerability data.
Analysis
by VulDB Data Team • 09/14/2026
The vulnerability identified in Samsung Mobile Processors within the Exynos series, specifically models 1330, 1380, 1480, 2400, 1580, and 2500, represents a critical memory safety flaw located within the camera subsystem. This issue stems from improper validation of input data directed at the test_msg sysfs entry. Sysfs is a pseudo-filesystem in Linux-based operating systems that provides an interface for exporting kernel objects to user space, often used for debugging or configuration purposes. In this context, the test_msg endpoint serves as a mechanism for sending diagnostic messages to the camera driver. The core technical flaw lies in the lack of rigorous bounds checking when processing these incoming messages. When a malformed message is transmitted through this entry point, the kernel code fails to verify that the data length and content are within acceptable limits before writing it into memory buffers allocated by the camera subsystem.
This absence of boundary validation results in an out-of-bounds write operation. An out-of-bounds write occurs when software writes data beyond the boundaries of a reserved block of memory, potentially overwriting adjacent memory locations that contain other variables, control structures, or even executable code. In the specific context of mobile SoCs like those from Samsung Exynos, such errors can corrupt critical kernel data structures associated with camera hardware initialization and operation. The immediate operational impact of this vulnerability is a denial of service condition. Because the corruption occurs within the kernel space handling sensitive hardware resources, it typically leads to system instability, causing the device to crash, reboot unexpectedly, or become unresponsive. For mobile devices relying on continuous availability for communication and safety-critical applications, such unpredictable behavior poses a significant risk to operational integrity.
From a classification perspective, this vulnerability aligns with CWE-787: Out-of-bounds Write, which describes writing data outside the bounds of an allocated buffer due to insufficient validation of input size or index values. Furthermore, given that the attack vector involves sending a malformed message via sysfs, it may also relate to CWE-20: Improper Input Validation, as the system fails to adequately sanitize and validate user-supplied data before processing. In terms of adversary tactics, this flaw could be leveraged in an ATT&CK framework context under techniques such as T1548: Abuse Elevation Control Mechanism if the attacker requires elevated privileges to access sysfs entries, or potentially contribute to privilege escalation scenarios if the memory corruption allows for control flow hijacking. However, based on the provided description, the primary confirmed impact is denial of service rather than arbitrary code execution.
Mitigation strategies for this vulnerability primarily involve patching the kernel source code responsible for handling the test_msg sysfs entry. Developers must implement strict input validation routines that check the length and content of incoming messages against predefined limits before any write operations are executed. Additionally, enabling compiler-based security features such as stack canaries or address space layout randomization (ASLR) can help mitigate the potential consequences of memory corruption by making exploitation more difficult. For end-users and device manufacturers, applying the latest firmware updates provided by Samsung is essential to ensure that these kernel-level patches are deployed. Security auditors should also review similar sysfs interfaces within mobile SoC drivers for analogous validation gaps to prevent recurrence in other subsystems.