CVE-2021-45485: High severity Linux Linux kernel vulnerability

Published May 31, 2021
·
Updated

An information leak flaw was found in the Linux kernel’s IPv6 implementation in the ipv6selectident in net/ipv6/outputcore.c function. The use of a small hash table in IP ID generation allows a remote attacker to reveal sensitive information.

Other sources

In the IPv6 implementation in the Linux kernel before 5.13.3, net/ipv6/outputcore.c has an information leak because of certain use of a hash table which, although big, doesn't properly consider that IPv6-based attackers can typically choose among many IPv6 source addresses.

Affected Software

187 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<0:4.18.0-305.65.1.rt7.137.el8_4
0:4.18.0-305.65.1.rt7.137.el8_4
redhat/kernel<0:4.18.0-305.65.1.el8_4
0:4.18.0-305.65.1.el8_4
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.22-16.12.25-1
Linux Linux kernel<5.13.3
NetApp E-Series SANtricity OS Controller
NetApp Solidfire\, Enterprise Sds \& Hci Storage Node
NetApp Solidfire \& Hci Management Node
NetApp Brocade Fabric Operating System Firmware
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 All Flash Fabric-attached Storage 8300 Firmware
NetApp All Flash Fabric-attached Storage 8300
NetApp Fabric-attached Storage 8300 Firmware
NetApp Fabric-attached Storage 8300
NetApp All Flash Fabric-attached Storage 8700 Firmware
NetApp All Flash Fabric-attached Storage 8700
NetApp Fabric-attached Storage 8700 Firmware
NetApp Fabric-attached Storage 8700
NetApp Aff A400 Firmware
NetApp Aff A400
NetApp Fabric-attached Storage A400 Firmware
NetApp Fabric-attached Storage A400
NetApp Hci Compute Node Firmware
NetApp Hci Compute Node
NetApp H300e Firmware
NetApp H300e
NetApp H300s Firmware
NetApp H300s
NetApp H410c Firmware
NetApp H410c
NetApp H410s Firmware
NetApp H410s
NetApp H500e Firmware
NetApp H500e
NetApp H500s Firmware
NetApp H500s
NetApp H610c Firmware
NetApp H610c
NetApp H610s Firmware
NetApp H610s
NetApp H615c Firmware
NetApp H615c
NetApp H700e Firmware
NetApp H700e
NetApp H700s Firmware
NetApp H700s
All of the following
NetApp All Flash Fabric-attached Storage 8300 Firmware
NetApp All Flash Fabric-attached Storage 8300
All of the following
NetApp Fabric-attached Storage 8300 Firmware
NetApp Fabric-attached Storage 8300
All of the following
NetApp All Flash Fabric-attached Storage 8700 Firmware
NetApp All Flash Fabric-attached Storage 8700
All of the following
NetApp Fabric-attached Storage 8700 Firmware
NetApp Fabric-attached Storage 8700
All of the following
NetApp Aff A400 Firmware
NetApp Aff A400
All of the following
NetApp Fabric-attached Storage A400 Firmware
NetApp Fabric-attached Storage A400
All of the following
NetApp Hci Compute Node Firmware
NetApp Hci Compute Node
All of the following
NetApp H300e Firmware
NetApp H300e
All of the following
NetApp H300s Firmware
NetApp H300s
All of the following
NetApp H410c Firmware
NetApp H410c
All of the following
NetApp H410s Firmware
NetApp H410s
All of the following
NetApp H500e Firmware
NetApp H500e
All of the following
NetApp H500s Firmware
NetApp H500s
All of the following
NetApp H610c Firmware
NetApp H610c
All of the following
NetApp H610s Firmware
NetApp H610s
All of the following
NetApp H615c Firmware
NetApp H615c
All of the following
NetApp H700e Firmware
NetApp H700e
All of the following
NetApp H700s Firmware
NetApp H700s
redhat/kernel<5.14
5.14
Linux Linux kernel<4.4.276
Linux Linux kernel>=4.5<4.9.276
Linux Linux kernel>=4.10<4.14.240
Linux Linux kernel>=4.15<4.19.198
Linux Linux kernel>=4.20<5.4.133
Linux Linux kernel>=5.5<5.10.51
Linux Linux kernel>=5.11<5.12.18
Linux Linux kernel>=5.13<5.13.3
ubuntu/linux-aws<4.4.0-1099.104
4.4.0-1099.104
ubuntu/linux-azure<4.15.0-1123.136~14.04.1
4.15.0-1123.136~14.04.1
ubuntu/linux-lts-xenial<4.4.0-219.252~14.04.1
4.4.0-219.252~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-219.252
4.4.0-219.252
ubuntu/linux-aws<4.4.0-1135.149
4.4.0-1135.149
ubuntu/linux-aws-hwe<4.15.0-1111.118~16.04.1
4.15.0-1111.118~16.04.1
ubuntu/linux-azure<4.15.0-1123.136~16.04.1
4.15.0-1123.136~16.04.1
ubuntu/linux-gcp<4.15.0-1108.122~16.04.1
4.15.0-1108.122~16.04.1
ubuntu/linux-hwe<4.15.0-156.163~16.04.1
4.15.0-156.163~16.04.1
ubuntu/linux-kvm<4.4.0-1100.109
4.4.0-1100.109
ubuntu/linux-oracle<4.15.0-1080.88~16.04.1
4.15.0-1080.88~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1069.75
4.4.0-1069.75
ubuntu/linux-fips*
ubuntu/linux<4.15.0-156.163
4.15.0-156.163
ubuntu/linux-aws<4.15.0-1111.118
4.15.0-1111.118
ubuntu/linux-aws-5.4<5.4.0-1056.59~18.04.1
5.4.0-1056.59~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1123.136
4.15.0-1123.136
ubuntu/linux-azure-5.4<5.4.0-1058.60~18.04.1
5.4.0-1058.60~18.04.1
ubuntu/linux-dell300x<4.15.0-1027.32
4.15.0-1027.32
ubuntu/linux-gcp-4.15<4.15.0-1108.122
4.15.0-1108.122
ubuntu/linux-gcp-5.4<5.4.0-1052.56~18.04.1
5.4.0-1052.56~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1052.55~18.04.1
5.4.0-1052.55~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1023.24~18.04.1
5.4.0-1023.24~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-84.94~18.04.1
5.4.0-84.94~18.04.1
ubuntu/linux-kvm<4.15.0-1099.101
4.15.0-1099.101
ubuntu/linux-oracle<4.15.0-1080.88
4.15.0-1080.88
ubuntu/linux-oracle-5.4<5.4.0-1054.58~18.04.1
5.4.0-1054.58~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1043.47~18.04.1
5.4.0-1043.47~18.04.1
ubuntu/linux-raspi2<4.15.0-1095.101
4.15.0-1095.101
ubuntu/linux-snapdragon<4.15.0-1112.121
4.15.0-1112.121
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<4.15.0-2053.55
4.15.0-2053.55
ubuntu/linux-azure-fips<4.15.0-2035.39
4.15.0-2035.39
ubuntu/linux-fips<4.15.0-1069.78
4.15.0-1069.78
ubuntu/linux-gcp-fips<4.15.0-2018.20
4.15.0-2018.20
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-84.94
5.4.0-84.94
ubuntu/linux-aws<5.4.0-1056.59
5.4.0-1056.59
ubuntu/linux-aws-5.11<5.11.0-1019.20~20.04.1
5.11.0-1019.20~20.04.1
ubuntu/linux-azure<5.4.0-1058.60
5.4.0-1058.60
ubuntu/linux-azure-5.11<5.11.0-1017.18~20.04.1
5.11.0-1017.18~20.04.1
ubuntu/linux-bluefield<5.4.0-1019.22
5.4.0-1019.22
ubuntu/linux-gcp<5.4.0-1052.56
5.4.0-1052.56
ubuntu/linux-gcp-5.11<5.11.0-1020.22~20.04.1
5.11.0-1020.22~20.04.1
ubuntu/linux-gke<5.4.0-1052.55
5.4.0-1052.55
ubuntu/linux-gkeop<5.4.0-1023.24
5.4.0-1023.24
ubuntu/linux-kvm<5.4.0-1046.48
5.4.0-1046.48
ubuntu/linux-oem-5.10<5.10.0-1049.51
5.10.0-1049.51
ubuntu/linux-oem-5.13<5.13.0-1014.18
5.13.0-1014.18
ubuntu/linux-oracle<5.4.0-1054.58
5.4.0-1054.58
ubuntu/linux-oracle-5.11<5.11.0-1019.20~20.04.1
5.11.0-1019.20~20.04.1
ubuntu/linux-raspi<5.4.0-1043.47
5.4.0-1043.47
ubuntu/linux-riscv-5.11<5.11.0-1020.21~20.04.1
5.11.0-1020.21~20.04.1
ubuntu/linux-aws-5.8*
ubuntu/linux-azure-5.8*
ubuntu/linux-azure-fde-5.15<5.15.0-1114.123~20.04.1
5.15.0-1114.123~20.04.1
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<5.4.0-1033.38
5.4.0-1033.38
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 0:4.18.0-305.65.1.rt7.137.el8_4
  4. Upgrade

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

    Fixed in 0:4.18.0-305.65.1.el8_4
  5. Upgrade

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

    Fixed in 5.10.223-1Fixed in 5.10.234-1Fixed in 6.1.129-1Fixed in 6.1.135-1Fixed in 6.12.22-1Fixed in 6.12.25-1
  6. Upgrade

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

    Fixed in 5.14
  7. Upgrade

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

    Fixed in 4.4.0-1099.104
  8. Upgrade

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

    Fixed in 4.15.0-1123.136~14.04.1
  9. Upgrade

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

    Fixed in 4.4.0-219.252~14.04.1
  10. Upgrade

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

    Fixed in 4.4.0-219.252
  11. Upgrade

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

    Fixed in 4.4.0-1135.149
  12. Upgrade

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

    Fixed in 4.15.0-1111.118~16.04.1
  13. Upgrade

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

    Fixed in 4.15.0-1123.136~16.04.1
  14. Upgrade

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

    Fixed in 4.15.0-1108.122~16.04.1
  15. Upgrade

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

    Fixed in 4.15.0-156.163~16.04.1
  16. Upgrade

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

    Fixed in 4.4.0-1100.109
  17. Upgrade

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

    Fixed in 4.15.0-1080.88~16.04.1
  18. Upgrade

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

    Fixed in 4.4.0-1069.75
  19. Upgrade

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

    Fixed in 4.15.0-156.163
  20. Upgrade

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

    Fixed in 4.15.0-1111.118
  21. Upgrade

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

    Fixed in 5.4.0-1056.59~18.04.1
  22. Upgrade

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

    Fixed in 4.15.0-1123.136
  23. Upgrade

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

    Fixed in 5.4.0-1058.60~18.04.1
  24. Upgrade

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

    Fixed in 4.15.0-1027.32
  25. Upgrade

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

    Fixed in 4.15.0-1108.122
  26. Upgrade

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

    Fixed in 5.4.0-1052.56~18.04.1
  27. Upgrade

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

    Fixed in 5.4.0-1052.55~18.04.1
  28. Upgrade

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

    Fixed in 5.4.0-1023.24~18.04.1
  29. Upgrade

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

    Fixed in 5.4.0-84.94~18.04.1
  30. Upgrade

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

    Fixed in 4.15.0-1099.101
  31. Upgrade

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

    Fixed in 4.15.0-1080.88
  32. Upgrade

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

    Fixed in 5.4.0-1054.58~18.04.1
  33. Upgrade

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

    Fixed in 5.4.0-1043.47~18.04.1
  34. Upgrade

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

    Fixed in 4.15.0-1095.101
  35. Upgrade

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

    Fixed in 4.15.0-1112.121
  36. Upgrade

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

    Fixed in 4.15.0-2053.55
  37. Upgrade

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

    Fixed in 4.15.0-2035.39
  38. Upgrade

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

    Fixed in 4.15.0-1069.78
  39. Upgrade

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

    Fixed in 4.15.0-2018.20
  40. Upgrade

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

    Fixed in 5.4.0-84.94
  41. Upgrade

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

    Fixed in 5.4.0-1056.59
  42. Upgrade

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

    Fixed in 5.11.0-1019.20~20.04.1
  43. Upgrade

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

    Fixed in 5.4.0-1058.60
  44. Upgrade

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

    Fixed in 5.11.0-1017.18~20.04.1
  45. Upgrade

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

    Fixed in 5.4.0-1019.22
  46. Upgrade

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

    Fixed in 5.4.0-1052.56
  47. Upgrade

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

    Fixed in 5.11.0-1020.22~20.04.1
  48. Upgrade

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

    Fixed in 5.4.0-1052.55
  49. Upgrade

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

    Fixed in 5.4.0-1023.24
  50. Upgrade

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

    Fixed in 5.4.0-1046.48
  51. Upgrade

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

    Fixed in 5.10.0-1049.51
  52. Upgrade

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

    Fixed in 5.13.0-1014.18
  53. Upgrade

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

    Fixed in 5.4.0-1054.58
  54. Upgrade

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

    Fixed in 5.11.0-1019.20~20.04.1
  55. Upgrade

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

    Fixed in 5.4.0-1043.47
  56. Upgrade

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

    Fixed in 5.11.0-1020.21~20.04.1
  57. Upgrade

    Upgrade ubuntu/linux-azure-fde-5.15 to a version that resolves this vulnerability.

    Fixed in 5.15.0-1114.123~20.04.1
  58. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  59. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  60. Upgrade

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

    Fixed in 5.4.0-1033.38
  61. 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

May 31, 2021
CVE Published
12:00 AM
Dec 25, 2021
CVE Published
via MITRE·01:05 AM
Data Sourced
via MITRE·01:05 AM
Description
Data Sourced
via OSV·02:15 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·02:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 12, 2022
Data Sourced
via Red Hat·05:39 PM
DescriptionSeverityAffected Software
Apr 28, 2022
Exploit Published
via GitHub·07:38 AM

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-45485?

CVE-2021-45485 is classified as a medium severity information leak vulnerability in the Linux kernel.

2

How do I fix CVE-2021-45485?

To fix CVE-2021-45485, update to the latest kernel versions specified in the advisory, such as kernel version 5.14 or specific Red Hat versions.

3

Which versions of the Linux kernel are affected by CVE-2021-45485?

Affected versions include the Linux kernel prior to 5.14 and specific earlier Red Hat kernel packages.

4

What type of information can be leaked by CVE-2021-45485?

CVE-2021-45485 allows remote attackers to potentially reveal sensitive information from the system due to flawed IPv6 implementation.

5

Is CVE-2021-45485 easy to exploit?

CVE-2021-45485 requires a remote attacker to send crafted IPv6 packets, making it a moderate risk for exposure.

Company

Resources

Contact

SecAlerts Pty Ltd.
132 Wickham Terrace
Fortitude Valley,
QLD 4006, Australia
info@secalerts.co
By using SecAlerts services, you agree to our services end-user license agreement. This website is safeguarded by reCAPTCHA and governed by the Google Privacy Policy and Terms of Service. All names, logos, and brands of products are owned by their respective owners, and any usage of these names, logos, and brands for identification purposes only does not imply endorsement. If you possess any content that requires removal, please get in touch with us.
© 2026 SecAlerts Pty Ltd.
ABN: 70 645 966 203, ACN: 645 966 203