CVE-2020-10767

Se encontró un fallo en el kernel de Linux versiones anteriores a 5.8-rc1, en la implementación de la Enhanced IBPB (Indirect Branch Prediction Barrier). La mitigación de IBPB será desactivada cuando STIBP no esté disponible o cuando Enhanced Indirect Branch Restricted Speculation (IBRS) esté disponible. Este fallo permite a un atacante local llevar a cabo un ataque estilo de Spectre V2 cuando esta configuración está activa. La mayor amenaza de esta vulnerabilidad es la confidencialidad

A flaw was found in the Linux kernel’s implementation of the Enhanced IBPB (Indirect Branch Prediction Barrier). The IBPB mitigation will be disabled when STIBP is not available or when the Enhanced Indirect Branch Restricted Speculation (IBRS) is available. This flaw allows a local attacker to perform a Spectre V2 style attack when this configuration is active. The highest threat from this vulnerability is to confidentiality.

It was discovered that the network block device implementation in the Linux kernel did not properly check for error conditions in some situations. An attacker could possibly use this to cause a denial of service. It was discovered that the btrfs file system implementation in the Linux kernel did not properly validate file system metadata in some situations. An attacker could use this to construct a malicious btrfs image that, when mounted, could cause a denial of service. Various other issues were also addressed.