Red Hat, Inc. AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H

Red Hat, Inc. CWE-20

A flaw buffer overflow in the Linux kernel BPF subsystem was found in the way user running BPF script calling getsockopt. A local user could use this flaw to crash the system or possibly escalate their privileges on the system.

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.

https://access.redhat.com/errata/RHSA-2021:4140 [No Types Assigned]

https://access.redhat.com/errata/RHSA-2021:4356 [No Types Assigned]

https://access.redhat.com/security/cve/CVE-2021-20194 [No Types Assigned]