CVE-2022-1116 is an integer overflow or wraparound vulnerability (CWE-190) found in the io_uring subsystem of the Linux Kernel. io_uring is a relatively recent asynchronous I/O interface introduced to improve performance and scalability of I/O operations. The vulnerability affects Linux Kernel versions prior to 5.4.189 and versions starting from 5.4.24 onward, indicating some ambiguity in the affected range but primarily impacting kernels before 5.4.189. The flaw arises when an integer overflow occurs during internal calculations within io_uring, leading to memory corruption. This memory corruption can be exploited by a local attacker to escalate privileges to root, effectively bypassing normal security controls. Exploitation requires local access to the system, as the vulnerability is triggered by invoking io_uring system calls with crafted parameters that cause the integer overflow. There are no known exploits in the wild at the time of this report, and no official patches linked, though kernel versions 5.4.189 and later presumably include fixes. The vulnerability impacts confidentiality, integrity, and availability by allowing unauthorized root-level access, potentially leading to full system compromise. The issue is classified as medium severity by the source, but given the privilege escalation vector and local exploit requirement, the risk is significant especially in multi-user or shared environments.

For European organizations, the impact of CVE-2022-1116 can be substantial, particularly for enterprises and service providers running Linux-based servers or workstations with vulnerable kernel versions. Successful exploitation grants attackers root privileges, enabling them to install malware, exfiltrate sensitive data, disrupt services, or pivot within the network. This is critical for sectors with high-value data such as finance, healthcare, government, and critical infrastructure. Organizations relying on Linux for cloud infrastructure, container hosts, or edge devices are at risk of lateral movement and persistent compromise. The local access requirement somewhat limits remote exploitation, but insider threats or compromised user accounts can leverage this vulnerability to escalate privileges. Given the widespread use of Linux in European data centers and enterprises, unpatched systems could lead to breaches impacting data protection compliance (e.g., GDPR) and operational continuity.

1. Immediate patching: Upgrade Linux kernels to versions 5.4.189 or later where the vulnerability is fixed. If using long-term support (LTS) distributions, apply vendor-provided security patches promptly. 2. Restrict local access: Limit user accounts with shell access and enforce strict access controls to reduce the risk of local exploitation. 3. Monitor system calls: Employ kernel-level monitoring tools or security modules (e.g., SELinux, AppArmor) to detect abnormal io_uring usage patterns. 4. Harden container and virtualization environments: Since many containers share the host kernel, ensure host kernels are patched and restrict container capabilities to prevent privilege escalation. 5. Conduct regular vulnerability scanning and penetration testing focusing on privilege escalation vectors. 6. Implement robust logging and alerting to detect suspicious local activity that could indicate exploitation attempts. 7. Educate system administrators and users about the risks of local privilege escalation vulnerabilities and the importance of applying updates.