CVE-2023-1073 is a memory corruption vulnerability classified under CWE-119, affecting the Linux kernel's Human Interface Device (HID) subsystem. This flaw arises when a local user inserts a malicious USB device, which triggers improper handling within the HID subsystem, leading to memory corruption. The vulnerability allows an attacker with local access and low privileges to cause a system crash (denial of service) or potentially escalate their privileges to gain higher-level access on the affected system. The vulnerability does not require user interaction beyond the insertion of the malicious USB device, and the attack vector is local (physical or logical access to the machine). The CVSS 3.1 base score is 6.6, indicating a medium severity level, with the vector string AV:P/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H. This means the attack requires local access with low complexity, privileges required are low, no user interaction is needed, and the impact on confidentiality, integrity, and availability is high. The affected Linux kernel versions are unspecified, but given the nature of the kernel HID subsystem, it likely affects multiple distributions and versions until patched. No known exploits are currently reported in the wild. The vulnerability was reserved in late February 2023 and published in late March 2023. The lack of patch links suggests that fixes may be pending or distributed through vendor-specific updates. This vulnerability is critical for environments where USB devices are frequently connected, especially in shared or multi-user systems, as it can be exploited by inserting a crafted USB device to compromise system security.

For European organizations, this vulnerability poses a significant risk especially in sectors where Linux systems are widely deployed, such as telecommunications, finance, research institutions, and government agencies. The ability to escalate privileges locally can lead to full system compromise, data breaches, or disruption of critical services. The high impact on confidentiality, integrity, and availability means sensitive data could be exposed or altered, and systems could be rendered inoperable. Organizations with lax physical security or those that allow users to connect external USB devices without restrictions are particularly vulnerable. The threat is exacerbated in environments with multi-user access or where endpoint security controls are weak. Additionally, the vulnerability could be leveraged in targeted attacks against critical infrastructure or high-value targets within Europe, potentially affecting national security or economic stability. The absence of known exploits in the wild currently reduces immediate risk but does not eliminate the threat, as proof-of-concept exploits could emerge. The medium CVSS score reflects the requirement for local access and privileges, limiting remote exploitation but not diminishing the severity in environments with insider threats or compromised endpoints.

1. Implement strict USB device control policies: Use endpoint security solutions that enforce whitelisting of authorized USB devices and block unauthorized or unknown devices from connecting. 2. Enhance physical security: Restrict physical access to critical systems to prevent unauthorized insertion of USB devices. 3. Apply kernel updates promptly: Monitor Linux distribution security advisories and apply patches as soon as they become available to remediate the vulnerability. 4. Employ privilege separation and least privilege principles: Limit user privileges to the minimum necessary to reduce the risk of privilege escalation. 5. Use USB device monitoring tools: Deploy tools that can detect anomalous USB device behavior or new device insertions and alert administrators in real-time. 6. Educate users: Train employees about the risks of connecting unknown USB devices and enforce policies against using untrusted peripherals. 7. Consider disabling USB ports where feasible, especially on systems that do not require USB device connectivity. 8. For virtualized environments, ensure that USB passthrough is controlled and monitored to prevent exploitation via virtual USB devices. These measures, combined, reduce the attack surface and limit the potential for exploitation of this vulnerability.