CVE-2023-52844 in Linux
Summary
by MITRE • 05/21/2024
In the Linux kernel, the following vulnerability has been resolved:
media: vidtv: psi: Add check for kstrdup
Add check for the return value of kstrdup() and return the error if it fails in order to avoid NULL pointer dereference.
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Analysis
by VulDB Data Team • 08/17/2025
The vulnerability identified as CVE-2023-52844 resides within the Linux kernel's media subsystem, specifically in the vidtv component responsible for processing Program Specific Information (PSI) data. This flaw represents a classic null pointer dereference vulnerability that could potentially lead to system instability or denial of service conditions. The vidtv subsystem handles television signal processing and PSI data parsing, which are critical components in digital television reception and processing within Linux-based systems. The vulnerability manifests in the psi module where string duplication operations are performed without proper validation of the allocation result.
The technical root cause of this vulnerability stems from insufficient error handling in the kstrdup() function call within the vidtv psi processing code. The kstrdup() function is a kernel utility that allocates memory and copies a string into the newly allocated space. When this function fails to allocate memory, it returns a NULL pointer instead of a valid memory address. The vulnerable code fails to check this return value before proceeding with operations that assume the string duplication was successful. This oversight creates a scenario where subsequent code attempts to dereference a NULL pointer, leading to kernel panic or system crash.
From an operational perspective, this vulnerability presents a significant risk to systems running Linux kernels with the affected media subsystem. The impact extends beyond simple denial of service to potentially compromising the stability of television reception systems, digital media processing applications, and any software that relies on the vidtv subsystem for signal processing. Attackers could exploit this vulnerability by crafting malicious PSI data that triggers the memory allocation failure, causing the kernel to crash and resulting in system unavailability. The vulnerability aligns with CWE-476 which specifically addresses null pointer dereference conditions in software development practices.
The mitigation strategy for CVE-2023-52844 involves implementing proper error handling mechanisms that check the return value of kstrdup() calls before proceeding with subsequent operations. This approach follows established security best practices for kernel development and aligns with the ATT&CK framework's defense evasion techniques by ensuring proper input validation and error handling. System administrators should prioritize updating their kernel versions to include the patched code that incorporates the necessary return value checks. The fix demonstrates the importance of robust error handling in kernel space operations and represents a fundamental security principle that should be applied throughout kernel development processes. This vulnerability serves as a reminder of the critical importance of thorough input validation and error checking in operating system components, particularly those handling multimedia data streams where malformed input could lead to system instability. The patch implementation resolves the issue by ensuring that when kstrdup() fails to allocate memory, the error is properly propagated back to the calling function rather than allowing execution to continue with a NULL pointer reference.