CVE-2022-48832 is a vulnerability identified in the Linux kernel's audit subsystem, specifically related to the handling of the openat2 system call arguments within the audit_match_perm() function. The vulnerability arises because the kernel code dereferences the openat2 syscall argument to obtain the open_how::flags directly, which can lead to an out-of-bounds memory access or page fault (kernel oops). This improper dereferencing occurs when checking permissions during auditing, and the flaw was reported by a security researcher named Jeff. The root cause is that the kernel attempts to access syscall arguments without proper validation or safe referencing, which can cause kernel instability or crashes. The patch resolves this by using a stored copy of the open_how structure within the audit_context, accessed via audit_openat2_how(), thereby avoiding unsafe dereferencing of syscall arguments. A similar fix was independently proposed by another developer shortly after the initial patch. This vulnerability affects Linux kernel versions identified by the commit hash 1c30e3af8a79260cdba833a719209b01e6b92300, indicating a specific code state rather than a broad version range. There are no known exploits in the wild at the time of publication, and no CVSS score has been assigned yet. The vulnerability is primarily a stability and denial-of-service risk rather than a direct privilege escalation or information disclosure vector. However, kernel crashes can lead to system downtime and potential disruption of services relying on Linux systems.

For European organizations, the impact of CVE-2022-48832 primarily involves potential denial-of-service conditions due to kernel crashes triggered by the vulnerability. Organizations running Linux-based servers, especially those utilizing audit subsystems for compliance and security monitoring, could experience unexpected system reboots or instability if the vulnerability is exploited. This can disrupt critical infrastructure, cloud services, and enterprise applications that rely on Linux kernels. While no direct privilege escalation or data breach is indicated, the loss of availability can affect business continuity, regulatory compliance (e.g., GDPR requirements for uptime and data integrity), and operational reliability. Industries such as finance, telecommunications, healthcare, and government agencies in Europe that depend heavily on Linux servers for backend operations and auditing may be particularly sensitive to such disruptions. Additionally, the vulnerability could be leveraged as part of a multi-stage attack to cause system instability, complicating incident response and forensic analysis.

European organizations should prioritize applying the official Linux kernel patches that address this vulnerability as soon as they are available and tested in their environments. Specifically, updating to kernel versions that include the fix for CVE-2022-48832 is critical. Organizations should also audit their use of the audit subsystem and openat2 syscall usage to identify any custom or legacy code that might interact with these components. Implementing kernel crash monitoring and automated reboot prevention mechanisms can help detect and mitigate the impact of potential exploitation attempts. Additionally, organizations should restrict access to systems with audit capabilities to trusted administrators only, minimizing the risk of malicious triggering of the vulnerability. Regularly reviewing kernel logs and audit logs for anomalies related to openat2 syscall usage can provide early warning signs. Finally, incorporating this vulnerability into incident response playbooks and ensuring that system backups and failover mechanisms are robust will reduce downtime in case of exploitation.