CVE-2021-33909

Un archivo fs/seq_file.c en el kernel de Linux versiones 3.16 hasta 5.13.x anteriores a 5.13.4, no restringe apropiadamente las asignaciones de búferes seq, conllevando a un desbordamiento de enteros, una escritura fuera de límites y una escalada a root por parte de un usuario no privilegiado, también se conoce como CID-8cae8cd89f05

An out-of-bounds write flaw was found in the Linux kernel's seq_file in the Filesystem layer. This flaw allows a local attacker with a user privilege to gain access to out-of-bound memory, leading to a system crash, leak of internal kernel information and can escalate privileges. The issue results from not validating the size_t-to-int conversion prior to performing operations. The highest threat from this vulnerability is to data integrity, confidentiality and system availability.