Уязвимость функции KD_FONT_OP_COPY драйвера fbcon ядра операционных систем Linux, позволяющая нарушителю повысить свои привилегии или вызвать отказ в обслуживании

A flaw was found in the JFS filesystem code in the Linux Kernel which allows a local attacker with the ability to set extended attributes to panic the system, causing memory corruption or escalating privileges. The highest threat from this vulnerability is to confidentiality, integrity, as well as system availability.

A slab-out-of-bounds read in fbcon in the Linux kernel before 5.9.7 could be used by local attackers to read privileged information or potentially crash the kernel, aka CID-3c4e0dff2095. This occurs because KD_FONT_OP_COPY in drivers/tty/vt/vt.c can be used for manipulations such as font height.