CVE-2022-49111 is a high-severity use-after-free vulnerability in the Linux kernel's Bluetooth subsystem, specifically within the hci_send_acl function. The flaw arises when the kernel receives the HCI_EV_DISCONN_PHY_LINK_COMPLETE event and calls hci_conn_del without verifying if the connection type is AMP_LINK. If it is, the kernel fails to properly clean up upper layers using hci_disconn_cfm, leading to a use-after-free condition. This vulnerability was detected by Kernel Address Sanitizer (KASAN), which reported an invalid memory read of a freed object. The root cause is improper handling of Bluetooth connection cleanup, where the kernel attempts to access memory that has already been freed. The vulnerability affects multiple Linux kernel versions identified by the same commit hash, indicating a specific code state. Exploitation requires local privileges with low complexity and no user interaction, as indicated by the CVSS vector (AV:L/AC:L/PR:L/UI:N). The impact includes full confidentiality, integrity, and availability compromise of the affected system due to the potential for arbitrary code execution or kernel crashes. No known exploits are currently reported in the wild, but the severity and nature of the bug make it a critical risk for systems relying on Bluetooth functionality. The vulnerability is categorized under CWE-416 (Use After Free), a common and dangerous memory corruption issue. The Linux kernel maintainers have resolved this issue, but no direct patch links are provided in the data. The detailed kernel stack traces and memory state dumps confirm the technical depth of the flaw and the complexity of the Bluetooth stack's connection management.

For European organizations, this vulnerability poses a significant risk, especially those operating Linux-based infrastructure with Bluetooth enabled. This includes enterprises using Linux servers, embedded systems, IoT devices, and mobile devices that rely on Bluetooth connectivity. Exploitation could lead to privilege escalation, allowing attackers to execute arbitrary code in kernel space, resulting in system compromise, data theft, or denial of service. Critical sectors such as manufacturing, healthcare, transportation, and telecommunications that utilize Linux-based Bluetooth-enabled devices could face operational disruptions. Additionally, organizations with remote or hybrid workforces using Linux laptops or devices with Bluetooth enabled are at risk of targeted attacks. The vulnerability's requirement for local privileges means that attackers need some level of access, but the low complexity and no user interaction required lower the barrier for exploitation by insiders or malware that gains initial foothold. The lack of known exploits in the wild provides a window for mitigation, but the high impact on confidentiality, integrity, and availability demands urgent attention.

1. Immediate application of Linux kernel updates that address CVE-2022-49111 is critical. Organizations should monitor official Linux kernel repositories and distributions for patches and apply them promptly. 2. Disable Bluetooth functionality on Linux systems where it is not required, reducing the attack surface. 3. For systems requiring Bluetooth, implement strict access controls to limit local user privileges and prevent unauthorized code execution. 4. Employ kernel hardening techniques such as Kernel Address Sanitizer (KASAN) in testing environments to detect similar memory corruption issues proactively. 5. Monitor system logs and kernel messages for unusual Bluetooth-related errors or crashes that may indicate exploitation attempts. 6. Use endpoint detection and response (EDR) tools capable of detecting anomalous kernel behavior or privilege escalation attempts. 7. Conduct regular security audits of Linux systems focusing on Bluetooth usage and kernel version compliance. 8. Educate system administrators and users about the risks of local privilege escalation vulnerabilities and enforce least privilege principles.