CVE-2024-26879 is a vulnerability identified in the Linux kernel related to the clock management subsystem, specifically within the Meson platform's clock register maps (axg_clk_regmaps). The issue arises from missing clock entries in the axg_clk_regmaps, which leads to a NULL pointer dereference when the kernel attempts to access these clocks. This dereference occurs during the execution of the command 'cat /sys/kernel/debug/clk/clk_summary', which is used to display clock information for debugging purposes. The kernel panic trace indicates that the fault happens in the regmap_read function, called by clk_regmap_gate_is_enabled, which is part of the clock core's enablement checking routines. The absence of certain clocks in the register map causes the kernel to attempt to read from a NULL pointer, resulting in a system crash (kernel panic). This vulnerability affects specific versions of the Linux kernel identified by the commit hash 14ebb3154b8f3d562cb18331b08ff1a22609ae59. The vulnerability does not appear to have known exploits in the wild at this time, and no CVSS score has been assigned. The root cause is a missing initialization or registration of clocks in the Meson platform's clock management code, which is critical for stable kernel operation on affected hardware platforms. The vulnerability is triggered by a local user or process reading the debug clock summary file, which is typically accessible only to privileged users. The fix involves adding the missing clocks to the axg_clk_regmaps to prevent the NULL pointer dereference and subsequent kernel panic.

For European organizations, the impact of CVE-2024-26879 depends largely on the deployment of affected Linux kernel versions on their infrastructure, particularly on devices using the Meson platform (commonly found in embedded systems and certain ARM-based devices). The vulnerability causes a kernel panic, leading to a denial of service (DoS) condition. This can disrupt critical services, especially in environments relying on embedded Linux devices for networking, industrial control, or IoT applications. While the vulnerability requires local access to trigger (reading a debug file), it could be exploited by an attacker who has gained limited access to a system to cause system instability or downtime. This may affect operational continuity, particularly in sectors such as manufacturing, telecommunications, and critical infrastructure where embedded Linux devices are prevalent. The lack of remote exploitability reduces the risk of widespread attacks but does not eliminate the threat from insider threats or lateral movement within networks. Additionally, kernel panics can lead to data loss or corruption if systems are not properly configured for graceful recovery. Organizations using Linux distributions that incorporate the affected kernel versions must prioritize patching to maintain system stability and security.

1. Immediate application of kernel patches or updates from Linux distributions that address CVE-2024-26879 is the primary mitigation step. Monitor vendor advisories for updated kernels that include the fix for missing clocks in axg_clk_regmaps. 2. Restrict access to /sys/kernel/debug/clk/clk_summary and other debug interfaces to trusted administrators only, minimizing the risk of accidental or malicious triggering of the vulnerability. 3. Implement strict access controls and monitoring on systems running affected kernels, especially embedded devices using the Meson platform, to detect unusual read operations or attempts to access debug files. 4. For embedded and IoT devices, ensure secure firmware update mechanisms are in place to facilitate timely patch deployment. 5. Conduct thorough inventory and asset management to identify devices running the affected kernel versions and prioritize remediation efforts accordingly. 6. Employ kernel crash dump analysis and monitoring tools to quickly detect and respond to kernel panics that may indicate exploitation attempts. 7. Where possible, isolate critical embedded devices from general network access to reduce the attack surface and limit potential exploitation vectors.