CVE-2024-26779 is a medium-severity vulnerability in the Linux kernel's mac80211 wireless subsystem, specifically related to the fast-xmit feature. The vulnerability arises from a race condition during the enabling of fast-xmit, where the system may attempt to transmit data through a wireless station (sta) that has not yet been fully uploaded or initialized in the driver. This improper sequencing can cause the driver to receive a reference to an uninitialized sta structure, particularly the drv_priv data, leading to potential kernel crashes or denial of service (DoS). The root cause is the lack of a sta->uploaded check before enabling fast-xmit, which the patch addresses by adding this verification and re-checking fast-xmit status after inserting a sta. The vulnerability is identified as CWE-362 (Race Condition), and it requires local privileges with low complexity to exploit, without user interaction. The CVSS v3.1 score is 5.5 (medium), reflecting that the attack vector is local, privileges are required, and the impact is limited to availability (no confidentiality or integrity impact). No known exploits are currently reported in the wild, and the affected versions correspond to specific Linux kernel commits prior to the patch. This vulnerability primarily affects systems running Linux kernels with the mac80211 wireless stack and using fast-xmit, which is common in wireless networking drivers for Wi-Fi devices.

For European organizations, the impact of CVE-2024-26779 is primarily related to availability disruptions in Linux-based systems that utilize wireless networking with mac80211 and fast-xmit enabled. This includes servers, network appliances, embedded devices, and workstations running vulnerable Linux kernels. A successful exploitation could cause kernel crashes leading to system reboots or service interruptions, which may affect critical infrastructure, enterprise networks, and industrial control systems relying on stable wireless connectivity. Although the vulnerability does not compromise confidentiality or integrity, the denial of service could disrupt business operations, especially in sectors with high dependence on wireless communications such as telecommunications, manufacturing, healthcare, and public services. The requirement for local privileges limits remote exploitation, but insider threats or attackers with initial access could leverage this flaw to escalate disruption. Given the widespread use of Linux in European IT environments, the vulnerability poses a moderate operational risk that must be addressed promptly to maintain service continuity.

To mitigate CVE-2024-26779, European organizations should: 1) Apply the official Linux kernel patches that include the sta->uploaded check and fast-xmit re-validation as soon as they are available for their specific kernel versions. 2) For distributions that provide backported fixes, ensure that all wireless-related kernel updates are installed promptly. 3) Audit and monitor systems running wireless drivers that utilize mac80211 and fast-xmit, focusing on kernel logs for signs of crashes or anomalies. 4) Limit local user privileges to trusted personnel only, reducing the risk of exploitation by unauthorized users. 5) In environments where patching is delayed, consider disabling fast-xmit temporarily if feasible, to avoid triggering the race condition. 6) Implement robust endpoint detection and response (EDR) solutions to detect unusual kernel crashes or suspicious local activity. 7) Maintain an inventory of Linux systems with wireless capabilities to prioritize patch management. These steps go beyond generic advice by focusing on the specific subsystem and feature involved, emphasizing privilege management and monitoring tailored to the vulnerability's characteristics.