UBUNTU-CVE-2021-20194

Advisory lineage Upstream: 1 Downstream: 4
Published: 23 Feb 2021, 23:15
Last modified:03 Jun 2026, 13:34

Vulnerability Summary

Overall Risk (default)
medium
31/100
CVSS Score
7.8 HIGH
3.1 (osv_ubuntu)
EPSS Score
No data
KEV
Not listed
Ransomware
No reports
Public exploits
None found
Dark Web
Not detected

Timeline

23 Feb 2021, 23:15
Published
Vulnerability first disclosed
03 Jun 2026, 13:34
Last Modified
Vulnerability information updated

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.

CVSS Metrics

  • v3.1HIGHScore: 7.8CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Affected Systems

  • ubuntulinux

    < 5.4.0-71.79

  • ubuntulinux-aws

    < 5.4.0-1043.45

  • ubuntulinux-aws-5.0

    all

  • ubuntulinux-aws-5.3

    all

  • ubuntulinux-aws-5.4

    < 5.4.0-1043.45~18.04.1

  • ubuntulinux-aws-fips

    < 5.4.0-1069.73+fips2 | all

  • ubuntulinux-azure

    all | < 5.4.0-1044.46

  • ubuntulinux-azure-5.3

    all

  • ubuntulinux-azure-5.4

    < 5.4.0-1044.46~18.04.1

  • ubuntulinux-azure-edge

    all

  • ubuntulinux-azure-fips

    < 5.4.0-1073.76+fips1 | all

  • ubuntulinux-bluefield

    all

  • ubuntulinux-gcp

    all | < 5.4.0-1041.44

  • ubuntulinux-gcp-5.3

    all

  • ubuntulinux-gcp-5.4

    < 5.4.0-1041.44~18.04.1

  • ubuntulinux-gcp-edge

    all

  • ubuntulinux-gcp-fips

    < 5.4.0-1067.71~20.04.1 | all

  • ubuntulinux-gke

    < 5.4.0-1041.43

  • ubuntulinux-gke-4.15

    all

  • ubuntulinux-gke-5.4

    < 5.4.0-1040.42~18.04.1

  • ubuntulinux-gkeop

    < 5.4.0-1013.14

  • ubuntulinux-gkeop-5.4

    < 5.4.0-1013.14~18.04.1

  • ubuntulinux-hwe

    all

  • ubuntulinux-hwe-5.4

    < 5.4.0-71.79~18.04.1

  • ubuntulinux-hwe-5.8

    < 5.8.0-45.51~20.04.1

  • ubuntulinux-hwe-edge

    all | all

  • ubuntulinux-intel-iot-realtime

    all

  • ubuntulinux-kvm

    < 5.4.0-1037.38

  • ubuntulinux-nvidia

    all

  • ubuntulinux-oem

    all

  • ubuntulinux-oem-5.10

    < 5.10.0-1017.18

  • ubuntulinux-oem-5.6

    < 5.6.0-1053.57

  • ubuntulinux-oracle

    < 5.4.0-1042.45

  • ubuntulinux-oracle-5.0

    all

  • ubuntulinux-oracle-5.3

    all

  • ubuntulinux-oracle-5.4

    < 5.4.0-1042.45~18.04.1

  • ubuntulinux-raspi

    < 5.4.0-1033.36

  • ubuntulinux-raspi-5.4

    < 5.4.0-1033.36~18.04.1

  • ubuntulinux-raspi-realtime

    all

  • ubuntulinux-raspi2

    all

  • ubuntulinux-realtime

    all

  • ubuntulinux-riscv

    all

  • ubuntulinux-riscv-5.8

    < 5.8.0-18.20~20.04.1

References (8)