CVE-2021-20194

Name: CVE-2021-20194
Creator: NVD / NIST
Published: 2021-02-23T23:15:13.1+00:00
License: https://creativecommons.org/publicdomain/zero/1.0/

HIGHCVSS 7.8/10EPSS 0.40%

Last modified Jun 17, 2026

CVE-2021-20194 is a high-severity vulnerability rated 7.8/10 on the CVSS scale. 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). EPSS estimates a 0.40% chance of exploitation in the next 30 days.

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.

Metrics

CVSS 3.1

7.8/10

CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

EPSS Probability

0.40%

31.5th percentile

Probability of exploitation in the next 30 days. Learn more

Weakness Enumeration

Affected Software

Vendor	Product	Versions
Linux	Linux Kernel	> 5.2
Redhat	Openshift Container Platform	4.4
Redhat	Openshift Container Platform	4.5
Redhat	Openshift Container Platform	4.6
Redhat	Enterprise Linux	8.0

References

https://bugzilla.redhat.com/show_bug.cgi?id=1912683Issue Tracking, Patch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20210326-0003/Third Party Advisory
https://bugzilla.redhat.com/show_bug.cgi?id=1912683Issue Tracking, Patch, Third Party Advisory
https://security.netapp.com/advisory/ntap-20210326-0003/Third Party Advisory

Timeline

Published: Feb 23, 2021
Last Modified: Jun 17, 2026
Status: Modified

Frequently Asked Questions

What is CVE-2021-20194?

How severe is CVE-2021-20194?

CVE-2021-20194 has a CVSS score of 7.8/10 (HIGH severity). The EPSS model estimates a 0.40% probability of exploitation in the next 30 days.

How do I fix CVE-2021-20194?

Check the vendor references and advisories linked above for patched versions and mitigation guidance. You can also run a Strix scan to test if your systems are affected.

Are you affected by CVE-2021-20194?

Run a free Strix scan to check your systems for this vulnerability.

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Source: NVD / NIST