K33484369 : Linux kernel vulnerability CVE-2021-20194

Security Advisory Description

There is a vulnerability in the linux kernel versions higher than 5.2 (if kernel compiled with config params CONFIG_BPF_SYSCALL=y , CONFIG_BPF=y , CONFIG_CGROUPS=y , CONFIG_CGROUP_BPF=y , CONFIG_HARDENED_USERCOPY not set, and BPF hook to getsockopt is registered). As result of BPF execution, the local user can trigger bug in __cgroup_bpf_run_filter_getsockopt() function that can lead to heap overflow (because of non-hardened usercopy). The impact of attack could be deny of service or possibly privileges escalation. (CVE-2021-20194)

Impact

An attacker may be able to exploit this vulnerability to cause a denial-of-service (DoS) or gain privileges with unauthorized access to view information or make modifications.