CVE-2021-43389: Out-of-bounds Read

Published Sep 24, 2021
·
Updated

An improper validation of an array index and out of bounds memory read in the Linux kernel's Integrated Services Digital Network (ISDN) functionality was found in the way users call ioctl CMTPCONNADD. A local user could use this flaw to crash the system or starve the resources causing denial of service.

Other sources

An issue was discovered in the Linux kernel before 5.14.15. There is an array-index-out-of-bounds flaw in the detachcapictr function in drivers/isdn/capi/kcapi.c.

There is an array-index-out-bounds bug in detachcapictr in drivers/isdn/capi/kcapi.c. During this process, the kernel thread would call detachcapictr() to detach a register controller. if the controller was not attached yet, detachcapictr() would trigger an array-index-out-bounds bug.

Reference:

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=1f3e2e97c003f80c4b087092b225c8787ff91e4d https://lore.kernel.org/netdev/CAFcO6XOvGQrRTaTkaJ0p3zR7y7nrAWD79r48=LBbOyrK9X-vA@mail.gmail.com/

— Red Hat

Affected Software

106 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
Linux Linux kernel<5.14.15
redhat Enterprise Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
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
redhat/linux kernel<5.15
5.15
ubuntu/linux-aws<4.4.0-1102.107
4.4.0-1102.107
ubuntu/linux-azure<4.15.0-1129.142~14.04.1
4.15.0-1129.142~14.04.1
ubuntu/linux-lts-xenial<4.4.0-222.255~14.04.1
4.4.0-222.255~14.04.1
ubuntu/linux*
ubuntu/linux<4.4.0-222.255
4.4.0-222.255
ubuntu/linux-aws<4.4.0-1138.152
4.4.0-1138.152
ubuntu/linux-aws-hwe<4.15.0-1118.125~16.04.1
4.15.0-1118.125~16.04.1
ubuntu/linux-azure<4.15.0-1129.142~16.04.1
4.15.0-1129.142~16.04.1
ubuntu/linux-gcp<4.15.0-1114.128~16.04.1
4.15.0-1114.128~16.04.1
ubuntu/linux-hwe<4.15.0-166.174~16.04.1
4.15.0-166.174~16.04.1
ubuntu/linux-kvm<4.4.0-1103.112
4.4.0-1103.112
ubuntu/linux-oracle<4.15.0-1085.93~16.04.1
4.15.0-1085.93~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1072.78
4.4.0-1072.78
ubuntu/linux-fips*
ubuntu/linux<4.15.0-166.174
4.15.0-166.174
ubuntu/linux-aws<4.15.0-1118.125
4.15.0-1118.125
ubuntu/linux-aws-5.4<5.4.0-1061.64~18.04.1
5.4.0-1061.64~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1129.142
4.15.0-1129.142
ubuntu/linux-azure-5.4<5.4.0-1065.68~18.04.1
5.4.0-1065.68~18.04.1
ubuntu/linux-dell300x<4.15.0-1033.38
4.15.0-1033.38
ubuntu/linux-gcp-4.15<4.15.0-1114.128
4.15.0-1114.128
ubuntu/linux-gcp-5.4<5.4.0-1059.63~18.04.1
5.4.0-1059.63~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1057.60~18.04.1
5.4.0-1057.60~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1029.30~18.04.2
5.4.0-1029.30~18.04.2
ubuntu/linux-hwe-5.4<5.4.0-92.103~18.04.2
5.4.0-92.103~18.04.2
ubuntu/linux-kvm<4.15.0-1105.107
4.15.0-1105.107
ubuntu/linux-oracle<4.15.0-1085.93
4.15.0-1085.93
ubuntu/linux-oracle-5.4<5.4.0-1059.63~18.04.1
5.4.0-1059.63~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1048.53~18.04.1
5.4.0-1048.53~18.04.1
ubuntu/linux-raspi2<4.15.0-1101.108
4.15.0-1101.108
ubuntu/linux-snapdragon<4.15.0-1118.127
4.15.0-1118.127
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<4.15.0-2059.61
4.15.0-2059.61
ubuntu/linux-azure-fips<4.15.0-2041.45
4.15.0-2041.45
ubuntu/linux-fips<4.15.0-1075.84
4.15.0-1075.84
ubuntu/linux-gcp-fips<4.15.0-2024.26
4.15.0-2024.26
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-92.103
5.4.0-92.103
ubuntu/linux-aws<5.4.0-1061.64
5.4.0-1061.64
ubuntu/linux-aws-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-azure<5.4.0-1065.68
5.4.0-1065.68
ubuntu/linux-azure-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-bluefield<5.4.0-1023.26
5.4.0-1023.26
ubuntu/linux-gcp<5.4.0-1059.63
5.4.0-1059.63
ubuntu/linux-gcp-5.11<5.11.0-1024.26~20.04.1
5.11.0-1024.26~20.04.1
ubuntu/linux-gke<5.4.0-1057.60
5.4.0-1057.60
ubuntu/linux-gkeop<5.4.0-1029.30
5.4.0-1029.30
ubuntu/linux-hwe-5.11<5.11.0-44.48~20.04.2
5.11.0-44.48~20.04.2
ubuntu/linux-hwe-5.13<5.13.0-23.23~20.04.2
5.13.0-23.23~20.04.2
ubuntu/linux-ibm<5.4.0-1010.11
5.4.0-1010.11
ubuntu/linux-kvm<5.4.0-1051.53
5.4.0-1051.53
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<5.14.0-1008.8
5.14.0-1008.8
ubuntu/linux-oracle<5.4.0-1059.63
5.4.0-1059.63
ubuntu/linux-oracle-5.11<5.11.0-1023.24~20.04.1
5.11.0-1023.24~20.04.1
ubuntu/linux-raspi<5.4.0-1048.53
5.4.0-1048.53
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-5.8*
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<5.4.0-1038.44
5.4.0-1038.44
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*
debian/linux
6.1.176-16.1.190-16.12.107-16.12.115-27.2.15-1

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/Linux kernel to a version that resolves this vulnerability.

    Fixed in 5.15
  4. Upgrade

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

    Fixed in 4.4.0-1102.107
  5. Upgrade

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

    Fixed in 4.15.0-1129.142~14.04.1
  6. Upgrade

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

    Fixed in 4.4.0-222.255~14.04.1
  7. Upgrade

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

    Fixed in 4.4.0-222.255
  8. Upgrade

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

    Fixed in 4.4.0-1138.152
  9. Upgrade

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

    Fixed in 4.15.0-1118.125~16.04.1
  10. Upgrade

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

    Fixed in 4.15.0-1129.142~16.04.1
  11. Upgrade

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

    Fixed in 4.15.0-1114.128~16.04.1
  12. Upgrade

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

    Fixed in 4.15.0-166.174~16.04.1
  13. Upgrade

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

    Fixed in 4.4.0-1103.112
  14. Upgrade

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

    Fixed in 4.15.0-1085.93~16.04.1
  15. Upgrade

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

    Fixed in 4.4.0-1072.78
  16. Upgrade

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

    Fixed in 4.15.0-166.174
  17. Upgrade

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

    Fixed in 4.15.0-1118.125
  18. Upgrade

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

    Fixed in 5.4.0-1061.64~18.04.1
  19. Upgrade

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

    Fixed in 4.15.0-1129.142
  20. Upgrade

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

    Fixed in 5.4.0-1065.68~18.04.1
  21. Upgrade

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

    Fixed in 4.15.0-1033.38
  22. Upgrade

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

    Fixed in 4.15.0-1114.128
  23. Upgrade

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

    Fixed in 5.4.0-1059.63~18.04.1
  24. Upgrade

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

    Fixed in 5.4.0-1057.60~18.04.1
  25. Upgrade

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

    Fixed in 5.4.0-1029.30~18.04.2
  26. Upgrade

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

    Fixed in 5.4.0-92.103~18.04.2
  27. Upgrade

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

    Fixed in 4.15.0-1105.107
  28. Upgrade

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

    Fixed in 4.15.0-1085.93
  29. Upgrade

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

    Fixed in 5.4.0-1059.63~18.04.1
  30. Upgrade

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

    Fixed in 5.4.0-1048.53~18.04.1
  31. Upgrade

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

    Fixed in 4.15.0-1101.108
  32. Upgrade

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

    Fixed in 4.15.0-1118.127
  33. Upgrade

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

    Fixed in 4.15.0-2059.61
  34. Upgrade

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

    Fixed in 4.15.0-2041.45
  35. Upgrade

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

    Fixed in 4.15.0-1075.84
  36. Upgrade

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

    Fixed in 4.15.0-2024.26
  37. Upgrade

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

    Fixed in 5.4.0-92.103
  38. Upgrade

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

    Fixed in 5.4.0-1061.64
  39. Upgrade

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

    Fixed in 5.11.0-1023.24~20.04.1
  40. Upgrade

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

    Fixed in 5.4.0-1065.68
  41. Upgrade

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

    Fixed in 5.11.0-1023.24~20.04.1
  42. Upgrade

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

    Fixed in 5.4.0-1023.26
  43. Upgrade

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

    Fixed in 5.4.0-1059.63
  44. Upgrade

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

    Fixed in 5.11.0-1024.26~20.04.1
  45. Upgrade

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

    Fixed in 5.4.0-1057.60
  46. Upgrade

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

    Fixed in 5.4.0-1029.30
  47. Upgrade

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

    Fixed in 5.11.0-44.48~20.04.2
  48. Upgrade

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

    Fixed in 5.13.0-23.23~20.04.2
  49. Upgrade

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

    Fixed in 5.4.0-1010.11
  50. Upgrade

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

    Fixed in 5.4.0-1051.53
  51. Upgrade

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

    Fixed in 5.10.0-1051.53
  52. Upgrade

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

    Fixed in 5.13.0-1026.32
  53. Upgrade

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

    Fixed in 5.14.0-1008.8
  54. Upgrade

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

    Fixed in 5.4.0-1059.63
  55. Upgrade

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

    Fixed in 5.11.0-1023.24~20.04.1
  56. Upgrade

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

    Fixed in 5.4.0-1048.53
  57. Upgrade

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

    Fixed in 5.11.0-1024.25~20.04.1
  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 5.4.0-1038.44
  61. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1
  62. 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 7.2.15-1
  63. Upgrade

    Upgrade Linux kernel to a version that resolves this vulnerability.

    Fixed in 5.14.15
  64. Configuration

    Prevent the isdn kernel module from being loaded automatically.

    Linux kernel isdn module module loading = blacklisted/disabled

Event History

Sep 24, 2021
CVE Published
12:00 AM
Oct 12, 2021
Data Sourced
via Red Hat·10:24 AM
DescriptionSeverityAffected Software
Nov 4, 2021
CVE Published
via MITRE·06:39 PM
Data Sourced
via MITRE·06:39 PM
Description
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-2021-43389?

CVE-2021-43389 has a severity rating that may allow local users to crash the system or cause denial of service.

2

How do I fix CVE-2021-43389?

To fix CVE-2021-43389, update to kernel-rt version 0:4.18.0-372.9.1.rt7.166.el8 or kernel version 0:4.18.0-372.9.1.el8.

3

Which systems are affected by CVE-2021-43389?

CVE-2021-43389 affects multiple Linux kernel versions and specific distributions such as Red Hat Enterprise Linux and Debian.

4

Can CVE-2021-43389 be exploited remotely?

CVE-2021-43389 is a local vulnerability, meaning it requires local access to exploit.

5

What versions of the Linux kernel are vulnerable to CVE-2021-43389?

Linux kernel versions up to 5.14.15 are vulnerable to CVE-2021-43389.

Company

Resources

Contact

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