CVE-2021-3348: Race Condition

Published Jan 28, 2021
·
Updated

A flaw was found in the Linux kernel. A race codition in nbd ioctl may lead to a use-after-free read in nbdqueuerq causing a crash.

Upstream patch:

https://lore.kernel.org/linux-block/24dff677353e2e30a71d8b66c4dffdbdf77c4dbd.1611595239.git.josef@toxicpanda.com/

References:

https://www.openwall.com/lists/oss-security/2021/01/28/3

Other sources

nbdaddsocket in drivers/block/nbd.c in the Linux kernel through 5.10.12 has an ndbqueuerq use-after-free that could be triggered by local attackers (with access to the nbd device) via an I/O request at a certain point during device setup, aka CID-b98e762e3d71.

— Launchpad

Affected Software

73 affected componentsFixes available
Linux Linux kernel<=5.10.12
Debian Debian Linux=9.0
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-16.12.27-1
ubuntu/linux-azure<4.15.0-1112.124~14.04.1
4.15.0-1112.124~14.04.1
ubuntu/linux-aws-hwe<4.15.0-1098.105~16.04.1
4.15.0-1098.105~16.04.1
ubuntu/linux-azure<4.15.0-1112.124~16.04.1
4.15.0-1112.124~16.04.1
ubuntu/linux-gcp<4.15.0-1097.110~16.04.1
4.15.0-1097.110~16.04.1
ubuntu/linux-hwe<4.15.0-142.146~16.04.1
4.15.0-142.146~16.04.1
ubuntu/linux-oracle<4.15.0-1069.77~16.04.1
4.15.0-1069.77~16.04.1
ubuntu/linux-hwe-edge*
ubuntu/linux<4.15.0-141.145
4.15.0-141.145
ubuntu/linux-aws<4.15.0-1098.105
4.15.0-1098.105
ubuntu/linux-aws-5.4<5.4.0-1043.45~18.04.1
5.4.0-1043.45~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1112.125
4.15.0-1112.125
ubuntu/linux-azure-5.4<5.4.0-1044.46~18.04.1
5.4.0-1044.46~18.04.1
ubuntu/linux-dell300x<4.15.0-1016.20
4.15.0-1016.20
ubuntu/linux-gcp-4.15<4.15.0-1097.110
4.15.0-1097.110
ubuntu/linux-gcp-5.4<5.4.0-1041.44~18.04.1
5.4.0-1041.44~18.04.1
ubuntu/linux-gke-5.4<5.4.0-1040.42~18.04.1
5.4.0-1040.42~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1013.14~18.04.1
5.4.0-1013.14~18.04.1
ubuntu/linux-hwe-5.4<5.4.0-71.79~18.04.1
5.4.0-71.79~18.04.1
ubuntu/linux-kvm<4.15.0-1089.91
4.15.0-1089.91
ubuntu/linux-oracle<4.15.0-1069.77
4.15.0-1069.77
ubuntu/linux-oracle-5.4<5.4.0-1042.45~18.04.1
5.4.0-1042.45~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1033.36~18.04.1
5.4.0-1033.36~18.04.1
ubuntu/linux-raspi2<4.15.0-1083.88
4.15.0-1083.88
ubuntu/linux-snapdragon<4.15.0-1100.109
4.15.0-1100.109
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-gcp-edge*
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<4.15.0-2041.43
4.15.0-2041.43
ubuntu/linux-azure-fips<4.15.0-2024.27
4.15.0-2024.27
ubuntu/linux-fips<4.15.0-1057.65
4.15.0-1057.65
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-71.79
5.4.0-71.79
ubuntu/linux-aws<5.4.0-1043.45
5.4.0-1043.45
ubuntu/linux-azure<5.4.0-1044.46
5.4.0-1044.46
ubuntu/linux-gcp<5.4.0-1041.44
5.4.0-1041.44
ubuntu/linux-gke<5.4.0-1041.43
5.4.0-1041.43
ubuntu/linux-gkeop<5.4.0-1013.14
5.4.0-1013.14
ubuntu/linux-hwe-5.8<5.8.0-49.55~20.04.1
5.8.0-49.55~20.04.1
ubuntu/linux-kvm<5.4.0-1037.38
5.4.0-1037.38
ubuntu/linux-oem-5.10<5.10.0-1017.18
5.10.0-1017.18
ubuntu/linux-oracle<5.4.0-1042.45
5.4.0-1042.45
ubuntu/linux-raspi<5.4.0-1033.36
5.4.0-1033.36
ubuntu/linux-riscv-5.8<5.8.0-22.24~20.04.1
5.8.0-22.24~20.04.1
ubuntu/linux-oem-5.6*
ubuntu/linux-raspi2*
ubuntu/linux-riscv*
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-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-gcp-fips*
ubuntu/linux-intel-iot-realtime*
ubuntu/linux-realtime*
ubuntu/linux-raspi-realtime*
ubuntu/linux-vmware*

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. 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 6.12.25-1Fixed in 6.12.27-1
  2. Upgrade

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

    Fixed in 4.15.0-1112.124~14.04.1
  3. Upgrade

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

    Fixed in 4.15.0-1098.105~16.04.1
  4. Upgrade

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

    Fixed in 4.15.0-1112.124~16.04.1
  5. Upgrade

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

    Fixed in 4.15.0-1097.110~16.04.1
  6. Upgrade

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

    Fixed in 4.15.0-142.146~16.04.1
  7. Upgrade

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

    Fixed in 4.15.0-1069.77~16.04.1
  8. Upgrade

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

    Fixed in 4.15.0-141.145
  9. Upgrade

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

    Fixed in 4.15.0-1098.105
  10. Upgrade

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

    Fixed in 5.4.0-1043.45~18.04.1
  11. Upgrade

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

    Fixed in 4.15.0-1112.125
  12. Upgrade

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

    Fixed in 5.4.0-1044.46~18.04.1
  13. Upgrade

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

    Fixed in 4.15.0-1016.20
  14. Upgrade

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

    Fixed in 4.15.0-1097.110
  15. Upgrade

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

    Fixed in 5.4.0-1041.44~18.04.1
  16. Upgrade

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

    Fixed in 5.4.0-1040.42~18.04.1
  17. Upgrade

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

    Fixed in 5.4.0-1013.14~18.04.1
  18. Upgrade

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

    Fixed in 5.4.0-71.79~18.04.1
  19. Upgrade

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

    Fixed in 4.15.0-1089.91
  20. Upgrade

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

    Fixed in 4.15.0-1069.77
  21. Upgrade

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

    Fixed in 5.4.0-1042.45~18.04.1
  22. Upgrade

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

    Fixed in 5.4.0-1033.36~18.04.1
  23. Upgrade

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

    Fixed in 4.15.0-1083.88
  24. Upgrade

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

    Fixed in 4.15.0-1100.109
  25. Upgrade

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

    Fixed in 4.15.0-2041.43
  26. Upgrade

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

    Fixed in 4.15.0-2024.27
  27. Upgrade

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

    Fixed in 4.15.0-1057.65
  28. Upgrade

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

    Fixed in 5.4.0-71.79
  29. Upgrade

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

    Fixed in 5.4.0-1043.45
  30. Upgrade

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

    Fixed in 5.4.0-1044.46
  31. Upgrade

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

    Fixed in 5.4.0-1041.44
  32. Upgrade

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

    Fixed in 5.4.0-1041.43
  33. Upgrade

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

    Fixed in 5.4.0-1013.14
  34. Upgrade

    Upgrade ubuntu/linux-hwe-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-49.55~20.04.1
  35. Upgrade

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

    Fixed in 5.4.0-1037.38
  36. Upgrade

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

    Fixed in 5.10.0-1017.18
  37. Upgrade

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

    Fixed in 5.4.0-1042.45
  38. Upgrade

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

    Fixed in 5.4.0-1033.36
  39. Upgrade

    Upgrade ubuntu/linux-riscv-5.8 to a version that resolves this vulnerability.

    Fixed in 5.8.0-22.24~20.04.1
  40. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  41. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  42. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1
  43. Upgrade

    Upgrade linux kernel to a version that resolves this vulnerability.

    Fixed in 5.10.12Patch CID-b98e762e3d71
  44. Compensating control

    If local attackers have access to the nbd device, restrict access to the nbd device to trusted users/hosts (e.g., tighten device node permissions and/or control who can issue I/O requests to the /dev/nbd* device).

Event History

Jan 28, 2021
Data Sourced
via Red Hat·11:52 PM
DescriptionSeverityAffected Software
Feb 1, 2021
CVE Published
via MITRE·03:43 AM
Data Sourced
via MITRE·03:43 AM
Description
Data Sourced
via OSV·04:15 AM
DescriptionSeverityAffected Software
Data Sourced
via NVD·04:15 AM
RemedyDescriptionSeverityWeaknessAffected Software

Frequently Asked Questions

1

What is the severity of CVE-2021-3348?

CVE-2021-3348 has been classified as a moderate severity vulnerability.

2

How do I fix CVE-2021-3348?

To fix CVE-2021-3348, upgrade to a kernel version that is 5.10.223-1 or later, or 6.1.119-1 or later.

3

What systems are affected by CVE-2021-3348?

CVE-2021-3348 affects Linux Kernel versions up to and including 5.10.12 and Debian Linux version 9.0.

4

What type of vulnerability is CVE-2021-3348?

CVE-2021-3348 is a use-after-free vulnerability due to a race condition in the nbd ioctl.

5

Can CVE-2021-3348 lead to system crashes?

Yes, CVE-2021-3348 can lead to a system crash due to a use-after-free read in nbd_queue_rq.

Company

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