CVE-2018-25020

El subsistema BPF en el kernel de Linux versiones anteriores a 4.17, maneja inapropiadamente las situaciones con un salto largo sobre una secuencia de instrucciones donde las instrucciones internas requieren expansiones sustanciales en múltiples instrucciones BPF, conllevando a un desbordamiento. Esto afecta a los archivos kernel/bpf/core.c y net/core/filter.c

The BPF subsystem in the Linux kernel before 4.17 mishandles situations with a long jump over an instruction sequence where inner instructions require substantial expansions into multiple BPF instructions, leading to an overflow. This affects kernel/bpf/core.c and net/core/filter.c. Maxim Levitsky discovered that the KVM hypervisor implementation for AMD processors in the Linux kernel did not properly prevent a guest VM from enabling AVIC in nested guest VMs. An attacker in a guest VM could use this to write to portions of the host’s physical memory. Other vulnerabilities have also been addressed.