CVE-2021-27363: Infoleak

Published Feb 18, 2021
·
Updated

A flaw was found in the way access to sessions and handles was handled in the iSCSI driver in the Linux kernel. A local user could use this flaw to leak iSCSI transport handle kernel address or end arbitrary iSCSI connections on the system.

Other sources

A pointer leak was discovered in the linux kernel that can be used to determine the address of the iscsitransportstructure.

— Red Hat

An issue was discovered in the Linux kernel through 5.11.3. A kernel pointer leak can be used to determine the address of the iscsitransport structure. When an iSCSI transport is registered with the iSCSI subsystem, the transport's handle is available to unprivileged users via the sysfs file system, at /sys/class/iscsitransport/$TRANSPORTNAME/handle. When read, the showtransporthandle function (in drivers/scsi/scsitransportiscsi.c) is called, which leaks the handle. This handle is actually the pointer to an iscsitransport struct in the kernel module's global variables.

Affected Software

100 affected componentsFixes available
redhat/kernel-rt<0:3.10.0-1160.24.1.rt56.1161.el7
0:3.10.0-1160.24.1.rt56.1161.el7
redhat/kernel<0:3.10.0-1160.24.1.el7
0:3.10.0-1160.24.1.el7
redhat/kernel<0:3.10.0-327.96.1.el7
0:3.10.0-327.96.1.el7
redhat/kernel<0:3.10.0-514.88.1.el7
0:3.10.0-514.88.1.el7
redhat/kernel<0:3.10.0-693.84.1.el7
0:3.10.0-693.84.1.el7
redhat/kernel<0:3.10.0-957.72.1.el7
0:3.10.0-957.72.1.el7
redhat/kernel<0:3.10.0-1062.49.1.el7
0:3.10.0-1062.49.1.el7
redhat/kernel-rt<0:4.18.0-240.22.1.rt7.77.el8_3
0:4.18.0-240.22.1.rt7.77.el8_3
redhat/kernel<0:4.18.0-240.22.1.el8_3
0:4.18.0-240.22.1.el8_3
redhat/kernel<0:4.18.0-147.44.1.el8_1
0:4.18.0-147.44.1.el8_1
redhat/kernel-rt<0:4.18.0-193.51.1.rt13.101.el8_2
0:4.18.0-193.51.1.rt13.101.el8_2
redhat/kernel<0:4.18.0-193.51.1.el8_2
0:4.18.0-193.51.1.el8_2
Linux Linux kernel<=5.11.3
Debian Debian Linux=9.0
NetApp Cloud Backup
NetApp Solidfire Baseboard Management Controller Firmware
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.22-16.12.25-1
ubuntu/linux<3.13.0-185.236
3.13.0-185.236
ubuntu/linux-aws<4.4.0-1088.92
4.4.0-1088.92
ubuntu/linux-azure<4.15.0-1110.122~14.04.1
4.15.0-1110.122~14.04.1
ubuntu/linux-lts-xenial<4.4.0-206.238~14.04.1
4.4.0-206.238~14.04.1
ubuntu/linux<4.4.0-206.238
4.4.0-206.238
ubuntu/linux-aws<4.4.0-1124.138
4.4.0-1124.138
ubuntu/linux-aws-hwe<4.15.0-1096.103~16.04.1
4.15.0-1096.103~16.04.1
ubuntu/linux-azure<4.15.0-1110.122~16.04.1
4.15.0-1110.122~16.04.1
ubuntu/linux-gcp<4.15.0-1095.108~16.04.1
4.15.0-1095.108~16.04.1
ubuntu/linux-hwe<4.15.0-139.143~16.04.1
4.15.0-139.143~16.04.1
ubuntu/linux-kvm<4.4.0-1090.99
4.4.0-1090.99
ubuntu/linux-oracle<4.15.0-1067.75~16.04.1
4.15.0-1067.75~16.04.1
ubuntu/linux-raspi2<4.4.0-1148.158
4.4.0-1148.158
ubuntu/linux-snapdragon<4.4.0-1152.162
4.4.0-1152.162
ubuntu/linux-hwe-edge*
ubuntu/linux-fips<4.4.0-1058.64
4.4.0-1058.64
ubuntu/linux-fips*
ubuntu/linux<4.15.0-139.143
4.15.0-139.143
ubuntu/linux-aws<4.15.0-1096.103
4.15.0-1096.103
ubuntu/linux-aws-5.4<5.4.0-1041.43~18.04.1
5.4.0-1041.43~18.04.1
ubuntu/linux-azure-4.15<4.15.0-1110.122
4.15.0-1110.122
ubuntu/linux-azure-5.4<5.4.0-1043.45~18.04.1
5.4.0-1043.45~18.04.1
ubuntu/linux-dell300x<4.15.0-1015.19
4.15.0-1015.19
ubuntu/linux-gcp-4.15<4.15.0-1095.108
4.15.0-1095.108
ubuntu/linux-gcp-5.4<5.4.0-1040.43~18.04.1
5.4.0-1040.43~18.04.1
ubuntu/linux-gke-5.3<5.3.0-1041.44
5.3.0-1041.44
ubuntu/linux-gke-5.4<5.4.0-1039.41~18.04.1
5.4.0-1039.41~18.04.1
ubuntu/linux-gkeop-5.4<5.4.0-1012.13~18.04.1
5.4.0-1012.13~18.04.1
ubuntu/linux-hwe<5.3.0-72.68
5.3.0-72.68
ubuntu/linux-hwe-5.4<5.4.0-70.78~18.04.1
5.4.0-70.78~18.04.1
ubuntu/linux-kvm<4.15.0-1087.89
4.15.0-1087.89
ubuntu/linux-oracle<4.15.0-1067.75
4.15.0-1067.75
ubuntu/linux-oracle-5.4<5.4.0-1041.44~18.04.1
5.4.0-1041.44~18.04.1
ubuntu/linux-raspi-5.4<5.4.0-1032.35~18.04.1
5.4.0-1032.35~18.04.1
ubuntu/linux-raspi2<4.15.0-1081.86
4.15.0-1081.86
ubuntu/linux-raspi2-5.3<5.3.0-1038.40
5.3.0-1038.40
ubuntu/linux-snapdragon<4.15.0-1098.107
4.15.0-1098.107
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-edge*
ubuntu/linux-oem*
ubuntu/linux-oracle-5.0*
ubuntu/linux-oracle-5.3*
ubuntu/linux-aws-fips<4.15.0-2039.41
4.15.0-2039.41
ubuntu/linux-azure-fips<4.15.0-2022.25
4.15.0-2022.25
ubuntu/linux-fips<4.15.0-1055.63
4.15.0-1055.63
ubuntu/linux-aws-fips*
ubuntu/linux-azure-fips*
ubuntu/linux-fips*
ubuntu/linux-gcp-fips*
ubuntu/linux<5.4.0-70.78
5.4.0-70.78
ubuntu/linux-aws<5.4.0-1041.43
5.4.0-1041.43
ubuntu/linux-azure<5.4.0-1043.45
5.4.0-1043.45
ubuntu/linux-gcp<5.4.0-1040.43
5.4.0-1040.43
ubuntu/linux-gke<5.4.0-1039.41
5.4.0-1039.41
ubuntu/linux-gkeop<5.4.0-1012.13
5.4.0-1012.13
ubuntu/linux-hwe-5.8<5.8.0-48.54~20.04.1
5.8.0-48.54~20.04.1
ubuntu/linux-kvm<5.4.0-1036.37
5.4.0-1036.37
ubuntu/linux-oem-5.10<5.10.0-1019.20
5.10.0-1019.20
ubuntu/linux-oem-5.6<5.6.0-1052.56
5.6.0-1052.56
ubuntu/linux-oracle<5.4.0-1041.44
5.4.0-1041.44
ubuntu/linux-raspi<5.4.0-1032.35
5.4.0-1032.35
ubuntu/linux-riscv-5.8<5.8.0-20.22~20.04.1
5.8.0-20.22~20.04.1
ubuntu/linux-azure-fde-5.15<5.15.0-1114.123~20.04.1
5.15.0-1114.123~20.04.1
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 redhat/kernel-rt to a version that resolves this vulnerability.

    Fixed in 0:3.10.0-1160.24.1.rt56.1161.el7
  2. Upgrade

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

    Fixed in 0:3.10.0-1160.24.1.el7
  3. Upgrade

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

    Fixed in 0:3.10.0-327.96.1.el7
  4. Upgrade

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

    Fixed in 0:3.10.0-514.88.1.el7
  5. Upgrade

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

    Fixed in 0:3.10.0-693.84.1.el7
  6. Upgrade

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

    Fixed in 0:3.10.0-957.72.1.el7
  7. Upgrade

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

    Fixed in 0:3.10.0-1062.49.1.el7
  8. Upgrade

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

    Fixed in 0:4.18.0-240.22.1.rt7.77.el8_3
  9. Upgrade

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

    Fixed in 0:4.18.0-240.22.1.el8_3
  10. Upgrade

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

    Fixed in 0:4.18.0-147.44.1.el8_1
  11. Upgrade

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

    Fixed in 0:4.18.0-193.51.1.rt13.101.el8_2
  12. Upgrade

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

    Fixed in 0:4.18.0-193.51.1.el8_2
  13. 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
  14. Upgrade

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

    Fixed in 3.13.0-185.236
  15. Upgrade

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

    Fixed in 4.4.0-1088.92
  16. Upgrade

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

    Fixed in 4.15.0-1110.122~14.04.1
  17. Upgrade

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

    Fixed in 4.4.0-206.238~14.04.1
  18. Upgrade

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

    Fixed in 4.4.0-206.238
  19. Upgrade

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

    Fixed in 4.4.0-1124.138
  20. Upgrade

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

    Fixed in 4.15.0-1096.103~16.04.1
  21. Upgrade

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

    Fixed in 4.15.0-1110.122~16.04.1
  22. Upgrade

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

    Fixed in 4.15.0-1095.108~16.04.1
  23. Upgrade

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

    Fixed in 4.15.0-139.143~16.04.1
  24. Upgrade

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

    Fixed in 4.4.0-1090.99
  25. Upgrade

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

    Fixed in 4.15.0-1067.75~16.04.1
  26. Upgrade

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

    Fixed in 4.4.0-1148.158
  27. Upgrade

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

    Fixed in 4.4.0-1152.162
  28. Upgrade

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

    Fixed in 4.4.0-1058.64
  29. Upgrade

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

    Fixed in 4.15.0-139.143
  30. Upgrade

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

    Fixed in 4.15.0-1096.103
  31. Upgrade

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

    Fixed in 5.4.0-1041.43~18.04.1
  32. Upgrade

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

    Fixed in 4.15.0-1110.122
  33. Upgrade

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

    Fixed in 5.4.0-1043.45~18.04.1
  34. Upgrade

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

    Fixed in 4.15.0-1015.19
  35. Upgrade

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

    Fixed in 4.15.0-1095.108
  36. Upgrade

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

    Fixed in 5.4.0-1040.43~18.04.1
  37. Upgrade

    Upgrade ubuntu/linux-gke-5.3 to a version that resolves this vulnerability.

    Fixed in 5.3.0-1041.44
  38. Upgrade

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

    Fixed in 5.4.0-1039.41~18.04.1
  39. Upgrade

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

    Fixed in 5.4.0-1012.13~18.04.1
  40. Upgrade

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

    Fixed in 5.3.0-72.68
  41. Upgrade

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

    Fixed in 5.4.0-70.78~18.04.1
  42. Upgrade

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

    Fixed in 4.15.0-1087.89
  43. Upgrade

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

    Fixed in 4.15.0-1067.75
  44. Upgrade

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

    Fixed in 5.4.0-1041.44~18.04.1
  45. Upgrade

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

    Fixed in 5.4.0-1032.35~18.04.1
  46. Upgrade

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

    Fixed in 4.15.0-1081.86
  47. Upgrade

    Upgrade ubuntu/linux-raspi2-5.3 to a version that resolves this vulnerability.

    Fixed in 5.3.0-1038.40
  48. Upgrade

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

    Fixed in 4.15.0-1098.107
  49. Upgrade

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

    Fixed in 4.15.0-2039.41
  50. Upgrade

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

    Fixed in 4.15.0-2022.25
  51. Upgrade

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

    Fixed in 4.15.0-1055.63
  52. Upgrade

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

    Fixed in 5.4.0-70.78
  53. Upgrade

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

    Fixed in 5.4.0-1041.43
  54. Upgrade

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

    Fixed in 5.4.0-1043.45
  55. Upgrade

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

    Fixed in 5.4.0-1040.43
  56. Upgrade

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

    Fixed in 5.4.0-1039.41
  57. Upgrade

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

    Fixed in 5.4.0-1012.13
  58. Upgrade

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

    Fixed in 5.8.0-48.54~20.04.1
  59. Upgrade

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

    Fixed in 5.4.0-1036.37
  60. Upgrade

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

    Fixed in 5.10.0-1019.20
  61. Upgrade

    Upgrade ubuntu/linux-oem-5.6 to a version that resolves this vulnerability.

    Fixed in 5.6.0-1052.56
  62. Upgrade

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

    Fixed in 5.4.0-1041.44
  63. Upgrade

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

    Fixed in 5.4.0-1032.35
  64. Upgrade

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

    Fixed in 5.8.0-20.22~20.04.1
  65. 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
  66. Upgrade

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

    Fixed in 5.4.0-1069.73+fips2
  67. Upgrade

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

    Fixed in 5.4.0-1073.76+fips1
  68. Upgrade

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

    Fixed in 5.4.0-1067.71~20.04.1
  69. Configuration

    Prevent the libiscsi module from loading by adding `install libiscsi /bin/true` to `/etc/modprobe.d/disable-libiscsi.conf`; this mitigation may not be suitable if iSCSI is required.

    libiscsi kernel modules module loading = disabled
  70. Operational

    Restart the system if the libiscsi modules are currently loaded.

Event History

Feb 18, 2021
Data Sourced
via Red Hat·10:33 AM
DescriptionSeverityAffected Software
Mar 5, 2021
CVE Published
12:00 AM
Mar 7, 2021
CVE Published
via MITRE·03:55 AM
Data Sourced
via MITRE·03:55 AM
Description
Data Sourced
via OSV·04:15 AM
DescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Frequently Asked Questions

1

What is the severity of CVE-2021-27363?

CVE-2021-27363 is classified as a medium severity vulnerability.

2

How do I fix CVE-2021-27363?

To remediate CVE-2021-27363, users should upgrade to the patched kernel versions specified in the security advisories.

3

What impact does CVE-2021-27363 have on Linux kernel operations?

CVE-2021-27363 allows local users to leak kernel addresses or disrupt iSCSI connections, potentially affecting system stability.

4

Which Linux kernel versions are vulnerable to CVE-2021-27363?

CVE-2021-27363 affects various Linux kernel versions prior to the patched releases, including versions 3.10 and 4.18.

5

Who is affected by CVE-2021-27363?

Local users of systems running vulnerable versions of the Linux kernel are at risk from CVE-2021-27363.

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