CVE-2018-20169

Se ha descubierto un problema en el kernel de Linux hasta antes de la versión 4.19.9. El subsistema USB gestiona de manera incorrecta las comprobaciones de tamaño durante la lectura de un descriptor extra, relacionado con __usb_get_extra_descriptor en drivers/usb/core/usb.c.

A flaw was discovered in the Linux kernel's USB subsystem in the __usb_get_extra_descriptor() function in the drivers/usb/core/usb.c which mishandles a size check during the reading of an extra descriptor data. By using a specially crafted USB device which sends a forged extra descriptor, an unprivileged user with physical access to the system can potentially cause a privilege escalation or trigger a system crash or lock up and thus to cause a denial of service (DoS).

Wen Xu discovered that the ext4 file system implementation in the Linux kernel could possibly perform an out of bounds write when updating the journal for an inline file. An attacker could use this to construct a malicious ext4 image that, when mounted, could cause a denial of service. Vasily Averin and Pavel Tikhomirov discovered that the cleancache subsystem of the Linux kernel did not properly initialize new files in some situations. A local attacker could use this to expose sensitive information. Various other issues were also addressed.