CVE-2009-3640

CVE-2009-3640 describes a NULL pointer dereference vulnerability in the KVM subsystem of the Linux kernel, specifically in the update_cr8_intercept function, affecting versions prior to 2.6.32-rc1. This flaw arises from improper handling of the absence of an Advanced Programmable Interrupt Controller (APIC). A local attacker can exploit this by calling kvm_vcpu_ioctl, leading to a denial of service (system crash) or potentially privilege escalation. With a CVSS score of 4.9 (AV:L/AC:L/Au:N/C:N/I:N/A:C), it is considered a local attack with low complexity, primarily impacting system availability. There is no evidence of active exploitation, public exploit code (Metasploit, Nuclei, ExploitDB), or significant community discussion or media coverage.