CVE-2021-45486: Infoleak

Published Mar 24, 2021
·
Updated

An information leak flaw was found in the Linux kernel’s IPv4 implementation in the iprtinit in net/ipv4/route.c function. The use of a small hash table in IP ID generation allows a remote attacker to reveal sensitive information.

Other sources

An information leak problem could be observed in iprtinit in net/ipv4/route.c in the IPv4 implementation. In this flaw, using a small hash table in IP ID generation could be abused by a patient remote attacker to reveal sensitive information.

Reference and upstream patch: https://arxiv.org/pdf/2112.09604.pdf https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git/commit/net/ipv4/route.c?id=aa6dd211e4b1dde9d5dc25d699d35f789ae7eeba

— Red Hat

In the IPv4 implementation in the Linux kernel before 5.12.4, net/ipv4/route.c has an information leak because the hash table is very small.

Affected Software

96 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
Linux Linux kernel<5.12.4
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
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-1
redhat/kernel<5.13
5.13
ubuntu/linux-aws<4.4.0-1103.108
4.4.0-1103.108
ubuntu/linux-azure<4.15.0-1123.136~14.04.1
4.15.0-1123.136~14.04.1
ubuntu/linux-lts-xenial<4.4.0-223.256~14.04.1
4.4.0-223.256~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-223.256
4.4.0-223.256
ubuntu/linux-aws<4.4.0-1139.153
4.4.0-1139.153
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<4.4.0-1104.113
4.4.0-1104.113
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<4.4.0-1073.79
4.4.0-1073.79
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<5.4.0-1051.53~18.04.1
5.4.0-1051.53~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1123.136
4.15.0-1123.136
ubuntu/linux-azure-5.4<5.4.0-1051.53~18.04.1
5.4.0-1051.53~18.04.1
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<5.4.0-1046.49~18.04.1
5.4.0-1046.49~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1046.48~18.04.1
5.4.0-1046.48~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1018.19~18.04.1
5.4.0-1018.19~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-77.86~18.04.1
5.4.0-77.86~18.04.1
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<5.4.0-1048.52~18.04.1
5.4.0-1048.52~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1038.41~18.04.1
5.4.0-1038.41~18.04.1
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<5.4.0-77.86
5.4.0-77.86
ubuntu/linux-aws<5.4.0-1051.53
5.4.0-1051.53
ubuntu/linux-azure<5.4.0-1051.53
5.4.0-1051.53
ubuntu/linux-bluefield<5.4.0-1013.16
5.4.0-1013.16
ubuntu/linux-gcp<5.4.0-1046.49
5.4.0-1046.49
ubuntu/linux-gke<5.4.0-1046.48
5.4.0-1046.48
ubuntu/linux-gkeop<5.4.0-1018.19
5.4.0-1018.19
ubuntu/linux-kvm<5.4.0-1041.42
5.4.0-1041.42
ubuntu/linux-oem-5.10<5.10.0-1032.33
5.10.0-1032.33
ubuntu/linux-oracle<5.4.0-1048.52
5.4.0-1048.52
ubuntu/linux-raspi<5.4.0-1038.41
5.4.0-1038.41
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<5.4.0-1028.32
5.4.0-1028.32
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 6.12.25-1
  6. Upgrade

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

    Fixed in 5.13
  7. Upgrade

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

    Fixed in 4.4.0-1103.108
  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 4.4.0-223.256~14.04.1
  10. Upgrade

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

    Fixed in 4.4.0-223.256
  11. Upgrade

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

    Fixed in 4.4.0-1139.153
  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 4.4.0-1104.113
  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 4.4.0-1073.79
  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 5.4.0-1051.53~18.04.1
  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 5.4.0-1051.53~18.04.1
  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 5.4.0-1046.49~18.04.1
  27. Upgrade

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

    Fixed in 5.4.0-1046.48~18.04.1
  28. Upgrade

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

    Fixed in 5.4.0-1018.19~18.04.1
  29. Upgrade

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

    Fixed in 5.4.0-77.86~18.04.1
  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 5.4.0-1048.52~18.04.1
  33. Upgrade

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

    Fixed in 5.4.0-1038.41~18.04.1
  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 5.4.0-77.86
  41. Upgrade

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

    Fixed in 5.4.0-1051.53
  42. Upgrade

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

    Fixed in 5.4.0-1051.53
  43. Upgrade

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

    Fixed in 5.4.0-1013.16
  44. Upgrade

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

    Fixed in 5.4.0-1046.49
  45. Upgrade

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

    Fixed in 5.4.0-1046.48
  46. Upgrade

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

    Fixed in 5.4.0-1018.19
  47. Upgrade

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

    Fixed in 5.4.0-1041.42
  48. Upgrade

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

    Fixed in 5.10.0-1032.33
  49. Upgrade

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

    Fixed in 5.4.0-1048.52
  50. Upgrade

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

    Fixed in 5.4.0-1038.41
  51. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  52. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  53. Upgrade

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

    Fixed in 5.4.0-1028.32
  54. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1
  55. Upgrade

    Upgrade Linux kernel to a version that resolves this vulnerability.

    Fixed in 5.12.4

Event History

Mar 24, 2021
CVE Published
12:00 AM
Dec 25, 2021
CVE Published
via MITRE·01:04 AM
Data Sourced
via MITRE·01:04 AM
Description
Data Sourced
via OSV·02:15 AM
DescriptionSeverityAffected Software
Jan 12, 2022
Data Sourced
via Red Hat·05:44 PM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-45486?

CVE-2021-45486 has been assigned a medium severity rating due to its potential for information leakage.

2

How do I fix CVE-2021-45486?

To remediate CVE-2021-45486, users should update their Linux kernel to one of the patched versions specified by their distribution, such as kernel-rt version 0:4.18.0-372.9.1.rt7.166.el8 or similar.

3

Which systems are affected by CVE-2021-45486?

CVE-2021-45486 affects various Linux kernel versions, particularly those prior to 5.13 and specific Red Hat and Oracle distributions.

4

What types of information can be leaked due to CVE-2021-45486?

CVE-2021-45486 can potentially leak sensitive information due to compromised IP ID generation in the kernel's IPv4 implementation.

5

Is there a workaround for CVE-2021-45486?

Currently, the recommended action for CVE-2021-45486 is to apply the latest kernel updates, as there are no specified workarounds.

Company

Resources

Contact

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