Buffer overflow in Linux Kernel

CVE-2021-20194

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.

Vulnerability class: Drupalgeddon 2 (CVE-2018-7600)

EPSS: 0.004 (32.7th percentile) — read the EPSS interpretation.

CVSS v3 metric

CVSS v3 base score 7.8 (High). Vector: CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H.

Affected products

Weakness classification (CWE)

Public proof-of-concept exploits

References

Frequently asked questions

What is CVE-2021-20194?
CVE-2021-20194 is a high-severity vulnerability in Linux Kernel, classified under Improper Input Validation. CVSS score: 7.8/10. Published 2021-02-23.
How severe is CVE-2021-20194?
High severity. CVSS v3 base score is 7.8 out of 10.
Is CVE-2021-20194 known to be exploited?
1 public proof-of-concept repositories are indexed. Not currently listed in the CISA KEV catalog.