CVE-2019-7222 in Linux
Summary
by MITRE
The KVM implementation in the Linux kernel through 4.20.5 has an Information Leak.
If you want to get best quality of vulnerability data, you may have to visit VulDB.
Analysis
by VulDB Data Team • 08/04/2023
The vulnerability identified as CVE-2019-7222 represents a critical information disclosure flaw within the Kernel-based Virtual Machine (KVM) subsystem of the Linux kernel version 4.20.5 and earlier. This issue specifically affects the virtualization infrastructure that enables hypervisor functionality on Linux systems, creating potential pathways for unauthorized data exposure. The vulnerability resides in how KVM handles certain memory management operations during virtual machine execution, particularly in the context of nested virtualization scenarios where guest operating systems may interact with hypervisor-level resources.
The technical flaw manifests through improper memory management handling within the KVM implementation, where sensitive kernel memory contents can be inadvertently exposed to unprivileged guest virtual machines. This occurs due to insufficient validation of memory access patterns and inadequate boundary checking during virtual machine memory operations. The vulnerability exploits weaknesses in the memory mapping mechanisms that govern how virtual machine memory is translated and accessed, allowing malicious guest operating systems to potentially read kernel memory regions that should remain protected. This type of information leak can expose sensitive data including cryptographic keys, user credentials, system configuration details, and other confidential information stored within kernel memory spaces.
The operational impact of CVE-2019-7222 extends beyond simple data exposure, as it can enable attackers to gain deeper insights into the underlying system architecture and potentially facilitate more sophisticated attacks. When exploited successfully, this vulnerability allows for privilege escalation and can compromise the integrity of the entire virtualization environment. The implications are particularly severe in cloud computing environments where multiple tenants share the same physical hardware, as a compromised guest virtual machine could potentially access data belonging to other virtual machines running on the same host. This vulnerability directly violates fundamental security principles of isolation and containment that virtualization platforms are designed to enforce, creating potential for widespread compromise across virtualized infrastructures. The flaw aligns with CWE-200, which addresses information exposure, and can be categorized under ATT&CK technique T1059 for privilege escalation through kernel-level vulnerabilities.
Mitigation strategies for CVE-2019-7222 primarily involve applying the patched kernel version that addresses the memory management flaw in KVM implementation. System administrators should prioritize updating their Linux kernels to versions 4.20.6 or later, which contain the necessary fixes for this vulnerability. Organizations running virtualized environments should also implement additional monitoring and access controls to detect potential exploitation attempts. The patch addresses the root cause by implementing proper memory boundary checking and validation mechanisms that prevent unauthorized access to kernel memory regions. Security teams should conduct thorough vulnerability assessments of their virtualization infrastructure to identify systems potentially affected by this vulnerability and ensure comprehensive testing of the applied patches in production environments. Regular security updates and patch management processes should be maintained to prevent similar vulnerabilities from emerging in the virtualization stack.