Welcome to a detailed exploration of a critical security vulnerability found in the Linux kernel, specifically affecting the EXT4 filesystem. Identified by the Common Vulnerabilities and Exposures (CVE) ID CVE-2024-47701, this high-severity vulnerability has been assigned a CVSS (Common Vulnerability Scoring System) score of 7.8, indicating its significant impact potential. In this article, we will break down the nature of the problem, affected systems, and how it's being mitigated, ensuring that customers of LinuxPatch stay informed and protected.
The CVE-2024-47701 pertains to an out-of-bounds (OOB) access vulnerability in the Linux kernel's EXT4 filesystem code. Specifically, it impacts the functionality where inlined directory entries are managed. The vulnerability arises when the e_value_offs (offset within the block where the directory entry value starts) changes unexpectedly due to external modifications to the block device. Such changes can trigger an out-of-bounds operation during entry lookup, leading to use-after-free errors detected by KASAN (KernelAddressSanitizer), a dynamic memory error detector for the Linux kernel.
This is not just a theoretical concern; occurrences in real-world scenarios could cripple essential system functionalities, lead to data corruption, or even expose sensitive information if exploited by an attacker. Considering that EXT4 is commonly used due to its robustness and performance, the severity of this issue is evident.
The error was first observed in the following trace:
BUG: KASAN: use-after-free in ext4_search_dir+0xf2/0x1c0 fs/ext4/namei.c:1500
This indicates a critical memory management error within the ext4 code module responsible for directory name lookup operations. The function ext4_search_dir attempts to read memory that has already been freed, leading to potential system instability or malicious exploitation.
Systems running affected versions of the Linux kernel are at risk until the patch is applied. The vulnerability is particularly worrisome because it can occur under regular usage conditions where file system operations on EXT4 partitions are commonplace. Potential impacts include but are not limited to:
The Linux community has responded quickly to address this vulnerability. A patch has been released that ensures changes in the e_value_offs during filesystem operations do not lead to out-of-bounds access. By securing the block device's integrity and adding checks before accessing directory entry values, the patch effectively mitigates the risk posed by CVE-2024-47701. Users and administrators are advised to apply this patch immediately to avoid potential exploits.
Understanding and mitigating CVE-2024-47701 is crucial for maintaining the integrity and security of Linux systems, particularly those utilizing the EXT4 filesystem. At LinuxPatch, keeping our customers secure is our top priority, and we strive to ensure that all pertinent security advisories are communicated effectively, helping you to safeguard your systems against any potential cyber threats.
For further details on patching your system or general inquiries about CVE-2024-47701, please contact LinuxPatch support. Stay updated, stay secure!