CVE-2019-8912

En el kernel de Linux, hasta la versión 4.20.11, af_alg_release() en crypto/af_alg.c no establece un valor NULL para cierto miembro de estructura, lo que conduce a un uso de memoria previamente liberada en sockfs_setattr.

In the Linux kernel af_alg_release() in crypto/af_alg.c neglects to set a NULL value for a certain structure member, which leads to a use-after-free (UAF) in sockfs_setattr. A local attacker can use this flaw to escalate privileges and take control of the system.

M. Vefa Bicakci and Andy Lutomirski discovered that the kernel did not properly set up all arguments to an error handler callback used when running as a paravirtualized guest. An unprivileged attacker in a paravirtualized guest VM could use this to cause a denial of service. It was discovered that the KVM implementation in the Linux kernel on ARM 64bit processors did not properly handle some ioctls. An attacker with the privilege to create KVM-based virtual machines could use this to cause a denial of service or execute arbitrary code in the host. Various other issues were also addressed.