CVE-2024-47715 is a vulnerability identified in the Linux kernel's wireless driver stack, specifically affecting the mt76 driver for MediaTek wireless chipsets, including the mt7915 and mt7986 devices. The root cause is a race condition and improper handling of the band index (band_idx) in the function mt7915_band_config() for certain hardware configurations (MT7975_ONE_ADIE or MT7976_ONE_ADIE). This leads to an out-of-bounds dereference of the phys array in the mt76_wcid_cleanup() function, which is indirectly indexed by band_idx via wcid->phy_idx. The dereference results in a kernel oops (crash) due to an attempt to read from an invalid memory address (0x24), causing a level 1 translation fault and a kernel panic on affected devices. The issue was introduced by commit 0335c034e726, which fixed a race condition related to checking the TX queue fill status but inadvertently caused this memory access violation. The vulnerability manifests when the hostapd process interacts with the wireless driver, potentially causing denial of service (DoS) through kernel crashes. The fix involves using the mt76_dev_phy() function to correctly map band_idx to the appropriate physical device for all hardware combinations, preventing invalid memory access. This vulnerability affects Linux kernel versions containing the specified commits and impacts devices using the affected MediaTek chipsets with the mt76 driver. No known exploits are reported in the wild as of the publication date (October 21, 2024).

For European organizations, this vulnerability poses a risk primarily to systems running Linux kernels with the affected mt76 wireless driver and using MediaTek mt7915 or mt7986 chipsets. Such systems include embedded devices, wireless access points, routers, and potentially IoT devices deployed in enterprise or industrial environments. The impact is mainly a denial of service through kernel crashes, which can disrupt network connectivity and availability of critical services relying on wireless communication. In environments where wireless infrastructure is essential, such as telecommunications, manufacturing, healthcare, and public services, this could lead to operational downtime and loss of productivity. Although the vulnerability does not appear to allow privilege escalation or remote code execution directly, the resulting instability could be exploited as part of a broader attack chain. The lack of known exploits reduces immediate risk, but the vulnerability's presence in widely used Linux kernels necessitates prompt remediation to maintain network reliability and security posture.

European organizations should prioritize updating their Linux kernel versions to include the patch that fixes CVE-2024-47715. Since the vulnerability is tied to specific commits, verifying kernel versions and applying vendor-supplied patches or mainline kernel updates is critical. For embedded or specialized devices, coordinate with hardware vendors to obtain firmware or driver updates that incorporate the fix. Additionally, organizations should audit their network infrastructure to identify devices using affected MediaTek chipsets and mt76 drivers. Where patching is delayed, consider isolating vulnerable devices from critical network segments or limiting access to trusted users to reduce exploitation risk. Monitoring kernel logs for oops or crash messages related to mt76 can help detect attempted exploitation or instability. Implementing robust network segmentation and access controls will further mitigate potential impacts. Finally, maintain up-to-date inventories of hardware and software to ensure timely identification and remediation of such vulnerabilities.