CVE-2021-4203: Race Condition

Published Sep 29, 2021
·
Updated

A use-after-free read flaw was found in sockgetsockopt() in net/core/sock.c due to SOPEERCRED and SOPEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privilege may lead to a system crash or a leak of internal kernel information.

In this, if the creds are replaced and freed at the wrong time, a use-after-free read occurs.

References:

https://lore.kernel.org/netdev/20210929225750.2548112-1-eric.dumazet@gmail.com/T/ https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=35306eb23814 https://bugs.chromium.org/p/project-zero/issues/detail?id=2230&can=7&q=modified-after%3Atoday-30&sort=-modified&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified%20Cve&cells=tiles&redir=1

Other sources

A use-after-free read flaw was found in sockgetsockopt() in net/core/sock.c due to SOPEERCRED and SOPEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privileges may crash the system or leak internal kernel information.

Affected Software

142 affected componentsFixes available
redhat/kernel-rt<0:4.18.0-372.9.1.rt7.166.el8
0:4.18.0-372.9.1.rt7.166.el8
redhat/kernel<0:4.18.0-372.9.1.el8
0:4.18.0-372.9.1.el8
redhat/kernel-rt<0:4.18.0-305.57.1.rt7.129.el8_4
0:4.18.0-305.57.1.rt7.129.el8_4
redhat/kernel<0:4.18.0-305.57.1.el8_4
0:4.18.0-305.57.1.el8_4
Linux Linux kernel<5.15
Linux Linux kernel=5.15
Linux Linux kernel=5.15-rc1
Linux Linux kernel=5.15-rc2
Linux Linux kernel=5.15-rc3
NetApp Active Iq Unified Manager Vmware Vsphere
NetApp E-Series SANtricity OS Controller>=11.0.0<=11.70.2
NetApp Element Software
NetApp Hci Management Node
NetApp Solidfire
All of the following
NetApp Bootstrap Os
NetApp Hci Compute Node
All of the following
NetApp A700s Firmware
NetApp A700s
All of the following
NetApp H300s Firmware
NetApp H300s
All of the following
NetApp H500s Firmware
NetApp H500s
All of the following
NetApp H700s Firmware
NetApp H700s
All of the following
NetApp H410s Firmware
NetApp H410s
All of the following
NetApp H410c Firmware
NetApp H410c
Oracle Communications Cloud Native Core Binding Support Function=22.1.3
Oracle Communications Cloud Native Core Network Exposure Function=22.1.1
Oracle Communications Cloud Native Core Policy=22.2.0
NetApp Bootstrap Os
NetApp Hci Compute Node
NetApp A700s Firmware
NetApp A700s
NetApp H300s Firmware
NetApp H300s
NetApp H500s Firmware
NetApp H500s
NetApp H700s Firmware
NetApp H700s
NetApp H410s Firmware
NetApp H410s
NetApp H410c Firmware
NetApp H410c
redhat/kernel<5.15
5.15
debian/linux
6.1.176-16.1.190-16.12.107-16.12.115-27.2.12-17.2.15-1
ubuntu/linux-aws<4.4.0-1117.123
4.4.0-1117.123
ubuntu/linux-azure<4.15.0-1127.140~14.04.1
4.15.0-1127.140~14.04.1
ubuntu/linux-lts-xenial<4.4.0-239.273~14.04.1
4.4.0-239.273~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-239.273
4.4.0-239.273
ubuntu/linux-aws<4.4.0-1155.170
4.4.0-1155.170
ubuntu/linux-aws-hwe<4.15.0-1116.123~16.04.1
4.15.0-1116.123~16.04.1
ubuntu/linux-azure<4.15.0-1127.140~16.04.1
4.15.0-1127.140~16.04.1
ubuntu/linux-gcp<4.15.0-1112.126~16.04.1
4.15.0-1112.126~16.04.1
ubuntu/linux-hwe<4.15.0-163.171~16.04.1
4.15.0-163.171~16.04.1
ubuntu/linux-kvm<4.4.0-1118.128
4.4.0-1118.128
ubuntu/linux-oracle<4.15.0-1084.92~16.04.1
4.15.0-1084.92~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1088.95
4.4.0-1088.95
ubuntu/linux-fips*
ubuntu/linux<4.15.0-163.171
4.15.0-163.171
ubuntu/linux-aws<4.15.0-1116.123
4.15.0-1116.123
ubuntu/linux-aws-5.4<5.4.0-1060.63~18.04.1
5.4.0-1060.63~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1127.140
4.15.0-1127.140
ubuntu/linux-azure-5.4<5.4.0-1064.67~18.04.1
5.4.0-1064.67~18.04.1
ubuntu/linux-dell300x<4.15.0-1031.36
4.15.0-1031.36
ubuntu/linux-gcp-4.15<4.15.0-1112.126
4.15.0-1112.126
ubuntu/linux-gcp-5.4<5.4.0-1058.62~18.04.1
5.4.0-1058.62~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1056.59~18.04.1
5.4.0-1056.59~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1027.28~18.04.1
5.4.0-1027.28~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-91.102~18.04.1
5.4.0-91.102~18.04.1
ubuntu/linux-kvm<4.15.0-1103.105
4.15.0-1103.105
ubuntu/linux-oracle<4.15.0-1084.92
4.15.0-1084.92
ubuntu/linux-oracle-5.4<5.4.0-1058.62~18.04.1
5.4.0-1058.62~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1047.52~18.04.1
5.4.0-1047.52~18.04.1
ubuntu/linux-raspi2<4.15.0-1099.106
4.15.0-1099.106
ubuntu/linux-snapdragon<4.15.0-1116.125
4.15.0-1116.125
ubuntu/linux-aws-5.0*
ubuntu/linux-aws-5.3*
ubuntu/linux-azure*
ubuntu/linux-azure-5.3*
ubuntu/linux-azure-edge*
ubuntu/linux-gcp*
ubuntu/linux-gcp-5.3*
ubuntu/linux-gke-4.15*
ubuntu/linux-hwe*
ubuntu/linux-hwe-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2057.59
4.15.0-2057.59
ubuntu/linux-azure-fips<4.15.0-2039.43
4.15.0-2039.43
ubuntu/linux-fips<4.15.0-1073.82
4.15.0-1073.82
ubuntu/linux-gcp-fips<4.15.0-2022.24
4.15.0-2022.24
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-91.102
5.4.0-91.102
ubuntu/linux-aws<5.4.0-1060.63
5.4.0-1060.63
ubuntu/linux-aws-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-azure<5.4.0-1064.67
5.4.0-1064.67
ubuntu/linux-azure-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-bluefield<5.4.0-1022.25
5.4.0-1022.25
ubuntu/linux-gcp<5.4.0-1058.62
5.4.0-1058.62
ubuntu/linux-gcp-5.11<5.11.0-1024.26~20.04.1
5.11.0-1024.26~20.04.1
ubuntu/linux-gke<5.4.0-1056.59
5.4.0-1056.59
ubuntu/linux-gkeop<5.4.0-1027.28
5.4.0-1027.28
ubuntu/linux-hwe-5.13<5.13.0-23.23~20.04.2
5.13.0-23.23~20.04.2
ubuntu/linux-ibm<5.4.0-1008.9
5.4.0-1008.9
ubuntu/linux-kvm<5.4.0-1050.52
5.4.0-1050.52
ubuntu/linux-oem-5.10<5.10.0-1051.53
5.10.0-1051.53
ubuntu/linux-oem-5.13<5.13.0-1026.32
5.13.0-1026.32
ubuntu/linux-oem-5.14<5.14.0-1007.7
5.14.0-1007.7
ubuntu/linux-oracle<5.4.0-1058.62
5.4.0-1058.62
ubuntu/linux-oracle-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-raspi<5.4.0-1047.52
5.4.0-1047.52
ubuntu/linux-riscv-5.11<5.11.0-1024.25~20.04.1
5.11.0-1024.25~20.04.1
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.8*
ubuntu/linux-gcp-5.8*
ubuntu/linux-hwe-5.11*
ubuntu/linux-hwe-5.8*
ubuntu/linux-intel-5.13*
ubuntu/linux-oem-5.6*
ubuntu/linux-oracle-5.8*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
ubuntu/linux-riscv-5.8*
ubuntu/linux-aws-fips<5.4.0-1069.73+fips2
5.4.0-1069.73+fips2
ubuntu/linux-azure-fips<5.4.0-1073.76+fips1
5.4.0-1073.76+fips1
ubuntu/linux-fips<5.4.0-1037.43
5.4.0-1037.43
ubuntu/linux-gcp-fips<5.4.0-1067.71~20.04.1
5.4.0-1067.71~20.04.1
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-raspi-realtime*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-372.9.1.rt7.166.el8
  2. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-372.9.1.el8
  3. Upgrade

    Upgrade redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-305.57.1.rt7.129.el8_4
  4. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 0:4.18.0-305.57.1.el8_4
  5. Upgrade

    Upgrade redhat/kernel to a version that resolves this vulnerability.

    Fixed in 5.15
  6. Upgrade

    Upgrade debian/linux to a version that resolves this vulnerability.

    Fixed in 6.1.176-1Fixed in 6.1.190-1Fixed in 6.12.107-1Fixed in 6.12.115-2Fixed in 7.2.12-1Fixed in 7.2.15-1
  7. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1117.123
  8. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1127.140~14.04.1
  9. Upgrade

    Upgrade ubuntu/linux-lts-xenial to a version that resolves this vulnerability.

    Fixed in 4.4.0-239.273~14.04.1
  10. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 4.4.0-239.273
  11. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.4.0-1155.170
  12. Upgrade

    Upgrade ubuntu/linux-aws-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-1116.123~16.04.1
  13. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 4.15.0-1127.140~16.04.1
  14. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 4.15.0-1112.126~16.04.1
  15. Upgrade

    Upgrade ubuntu/linux-hwe to a version that resolves this vulnerability.

    Fixed in 4.15.0-163.171~16.04.1
  16. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.4.0-1118.128
  17. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1084.92~16.04.1
  18. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.4.0-1088.95
  19. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 4.15.0-163.171
  20. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 4.15.0-1116.123
  21. Upgrade

    Upgrade ubuntu/linux-aws-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1060.63~18.04.1
  22. Upgrade

    Upgrade ubuntu/linux-azure-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1127.140
  23. Upgrade

    Upgrade ubuntu/linux-azure-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1064.67~18.04.1
  24. Upgrade

    Upgrade ubuntu/linux-dell300x to a version that resolves this vulnerability.

    Fixed in 4.15.0-1031.36
  25. Upgrade

    Upgrade ubuntu/linux-gcp-4.15 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1112.126
  26. Upgrade

    Upgrade ubuntu/linux-gcp-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1058.62~18.04.1
  27. Upgrade

    Upgrade ubuntu/linux-gke-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1056.59~18.04.1
  28. Upgrade

    Upgrade ubuntu/linux-gkeop-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1027.28~18.04.1
  29. Upgrade

    Upgrade ubuntu/linux-hwe-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-91.102~18.04.1
  30. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 4.15.0-1103.105
  31. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 4.15.0-1084.92
  32. Upgrade

    Upgrade ubuntu/linux-oracle-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1058.62~18.04.1
  33. Upgrade

    Upgrade ubuntu/linux-raspi-5.4 to a version that resolves this vulnerability.

    Fixed in 5.4.0-1047.52~18.04.1
  34. Upgrade

    Upgrade ubuntu/linux-raspi2 to a version that resolves this vulnerability.

    Fixed in 4.15.0-1099.106
  35. Upgrade

    Upgrade ubuntu/linux-snapdragon to a version that resolves this vulnerability.

    Fixed in 4.15.0-1116.125
  36. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2057.59
  37. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2039.43
  38. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-1073.82
  39. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 4.15.0-2022.24
  40. Upgrade

    Upgrade ubuntu/linux to a version that resolves this vulnerability.

    Fixed in 5.4.0-91.102
  41. Upgrade

    Upgrade ubuntu/linux-aws to a version that resolves this vulnerability.

    Fixed in 5.4.0-1060.63
  42. Upgrade

    Upgrade ubuntu/linux-aws-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1023.24~20.04.1
  43. Upgrade

    Upgrade ubuntu/linux-azure to a version that resolves this vulnerability.

    Fixed in 5.4.0-1064.67
  44. Upgrade

    Upgrade ubuntu/linux-azure-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1023.24~20.04.1
  45. Upgrade

    Upgrade ubuntu/linux-bluefield to a version that resolves this vulnerability.

    Fixed in 5.4.0-1022.25
  46. Upgrade

    Upgrade ubuntu/linux-gcp to a version that resolves this vulnerability.

    Fixed in 5.4.0-1058.62
  47. Upgrade

    Upgrade ubuntu/linux-gcp-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1024.26~20.04.1
  48. Upgrade

    Upgrade ubuntu/linux-gke to a version that resolves this vulnerability.

    Fixed in 5.4.0-1056.59
  49. Upgrade

    Upgrade ubuntu/linux-gkeop to a version that resolves this vulnerability.

    Fixed in 5.4.0-1027.28
  50. Upgrade

    Upgrade ubuntu/linux-hwe-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-23.23~20.04.2
  51. Upgrade

    Upgrade ubuntu/linux-ibm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1008.9
  52. Upgrade

    Upgrade ubuntu/linux-kvm to a version that resolves this vulnerability.

    Fixed in 5.4.0-1050.52
  53. Upgrade

    Upgrade ubuntu/linux-oem-5.10 to a version that resolves this vulnerability.

    Fixed in 5.10.0-1051.53
  54. Upgrade

    Upgrade ubuntu/linux-oem-5.13 to a version that resolves this vulnerability.

    Fixed in 5.13.0-1026.32
  55. Upgrade

    Upgrade ubuntu/linux-oem-5.14 to a version that resolves this vulnerability.

    Fixed in 5.14.0-1007.7
  56. Upgrade

    Upgrade ubuntu/linux-oracle to a version that resolves this vulnerability.

    Fixed in 5.4.0-1058.62
  57. Upgrade

    Upgrade ubuntu/linux-oracle-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1023.24~20.04.1
  58. Upgrade

    Upgrade ubuntu/linux-raspi to a version that resolves this vulnerability.

    Fixed in 5.4.0-1047.52
  59. Upgrade

    Upgrade ubuntu/linux-riscv-5.11 to a version that resolves this vulnerability.

    Fixed in 5.11.0-1024.25~20.04.1
  60. Upgrade

    Upgrade ubuntu/linux-aws-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1069.73+fips2
  61. Upgrade

    Upgrade ubuntu/linux-azure-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1073.76+fips1
  62. Upgrade

    Upgrade ubuntu/linux-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1037.43
  63. Upgrade

    Upgrade ubuntu/linux-gcp-fips to a version that resolves this vulnerability.

    Fixed in 5.4.0-1067.71~20.04.1

Event History

Sep 29, 2021
CVE Published
12:00 AM
Jan 4, 2022
Data Sourced
via Red Hat·01:05 PM
DescriptionSeverityAffected Software
Mar 25, 2022
CVE Published
via MITRE·12:00 AM
Data Sourced
via MITRE·12:00 AM
DescriptionWeakness
Data Sourced
via OSV·07:15 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Peer vulnerabilities

Found alongside the following vulnerabilities.

Frequently Asked Questions

1

What is the severity of CVE-2021-4203?

CVE-2021-4203 is rated as having a high severity level due to its potential to cause system crashes or leak internal kernel information.

2

How do I fix CVE-2021-4203?

To remediate CVE-2021-4203, upgrade to the recommended kernel versions as specified in security advisories or vendor documentation.

3

What type of vulnerability is CVE-2021-4203?

CVE-2021-4203 is a use-after-free read flaw in the Linux kernel that can be exploited due to improper handling of socket options.

4

Who is affected by CVE-2021-4203?

Users of vulnerable versions of the Linux kernel, specifically those using certain Red Hat and Debian kernels, are at risk from CVE-2021-4203.

5

What conditions are necessary for CVE-2021-4203 to be exploited?

An attacker must have user privileges on the system to exploit CVE-2021-4203, allowing them to trigger the vulnerability.

Company

Resources

Contact

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