CVE-2024-35823 is a medium-severity vulnerability identified in the Linux kernel's virtual terminal (vt) subsystem. The issue arises from improper handling of overlapping memory buffers when deleting characters in the Unicode buffer of the virtual terminal. Specifically, the vulnerability is due to the use of memcpy() to move data within overlapping memory regions, which can cause buffer corruption. This flaw is similar to a previously fixed issue in the VGA text buffer, where memcpy() was replaced with memmove() to safely handle overlapping buffers. The vulnerability is categorized under CWE-120 (Classic Buffer Overflow), indicating a memory safety issue that can lead to buffer corruption. The CVSS v3.1 base score is 5.3, reflecting a medium severity level, with the vector indicating that the vulnerability can be exploited remotely (AV:N), requires low attack complexity (AC:L), no privileges (PR:N), no user interaction (UI:N), and impacts availability only (A:L) without affecting confidentiality or integrity. No known exploits are currently reported in the wild. The vulnerability affects specific Linux kernel versions identified by commit hashes, and the fix involves replacing memcpy() with memmove() to correctly handle overlapping buffers and prevent corruption. This vulnerability could potentially cause denial of service (DoS) conditions by crashing or destabilizing the virtual terminal subsystem when processing Unicode character deletions.

For European organizations relying on Linux-based systems, especially those using virtual terminals extensively (such as servers, embedded systems, or infrastructure devices), this vulnerability could lead to service disruptions. The impact is primarily on availability, as buffer corruption may cause crashes or instability in the virtual terminal subsystem, potentially leading to denial of service. While it does not directly compromise confidentiality or integrity, the resulting downtime could affect critical services, especially in sectors like finance, healthcare, telecommunications, and government where Linux servers are prevalent. Organizations using Linux distributions that have not yet applied the patch may be vulnerable to remote attacks that do not require authentication or user interaction, increasing the risk of automated exploitation attempts once public exploits emerge. The lack of known exploits currently limits immediate risk, but the ease of exploitation and remote attack vector suggest that proactive patching is important to maintain operational continuity.

European organizations should promptly update their Linux kernel to the latest patched versions that address CVE-2024-35823. Since the vulnerability is fixed by replacing memcpy() with memmove() in the vt subsystem, applying official kernel updates from trusted Linux distribution vendors is the most reliable mitigation. Organizations should: 1) Identify all Linux systems running affected kernel versions, especially those exposed to untrusted networks or providing remote access. 2) Prioritize patching servers and infrastructure devices that rely on virtual terminals. 3) Implement network segmentation and firewall rules to limit exposure of vulnerable systems to untrusted networks. 4) Monitor system logs and kernel messages for unusual crashes or instability in the vt subsystem that could indicate exploitation attempts. 5) Employ intrusion detection systems (IDS) tuned to detect anomalous behavior related to terminal buffer handling. 6) Maintain regular backups and incident response plans to quickly recover from potential denial of service incidents. 7) Coordinate with Linux distribution vendors for timely updates and advisories. Avoid applying unofficial patches or workarounds that may introduce instability.