CVE-2021-27364: Infoleak

Published Feb 18, 2021
·
Updated

A flaw was found in the Linux kernel. An out-of-bounds read was discovered in the libiscsi module that could lead to reading kernel memory or a crash. The highest threat from this vulnerability is to data confidentiality as well as system availability.

Other sources

An issue was discovered in the Linux kernel through 5.11.3. drivers/scsi/scsitransportiscsi.c is adversely affected by the ability of an unprivileged user to craft Netlink messages.

An out-of-bounds read was discovered in the Linux kernel in the libiscsi module (drivers/scsi/libiscsi.c). This bug is triggered via a call to sendpdu

Red Hat

Affected Software

34 affected componentsFixes available
redhat/kernel<0:2.6.32-754.39.1.el6
0:2.6.32-754.39.1.el6
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-alt<0:4.14.0-115.36.1.el7a
0:4.14.0-115.36.1.el7a
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
All of the following
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
Oracle Tekelec Platform Distribution>=7.4.0<=7.7.1
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=20.04
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.22-16.12.25-1
NetApp Cloud Backup
Linux Linux kernel<4.4.260
Linux Linux kernel>=4.5<4.9.260
Linux Linux kernel>=4.10<4.14.224
Linux Linux kernel>=4.15<4.19.179
Linux Linux kernel>=4.20<5.4.103
Linux Linux kernel>=5.5<5.10.21
Linux Linux kernel>=5.11<5.11.4

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 0:2.6.32-754.39.1.el6
  2. Upgrade

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

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

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

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

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

    Fixed in 0:4.14.0-115.36.1.el7a
  5. Upgrade

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

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

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

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

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

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

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

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

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

    Fixed in 0:3.10.0-1062.49.1.el7
  10. 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
  11. Upgrade

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

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

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

    Fixed in 0:4.18.0-147.44.1.el8_1
  13. 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
  14. Upgrade

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

    Fixed in 0:4.18.0-193.51.1.el8_2
  15. 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
  16. Configuration

    Disable the libiscsi kernel module from auto-loading by running: echo "install libiscsi /bin/true" >> /etc/modprobe.d/disable-libiscsi.conf. Note: this may not be suitable if the system requires iSCSI to function; restart the system if the libiscsi modules are already loaded.

    Linux kernel libiscsi (modprobe/module loading) /etc/modprobe.d/disable-libiscsi.conf (install rule for libiscsi) = /bin/true

Event History

Feb 18, 2021
Data Sourced
via Red Hat·10:34 AM
DescriptionSeverityAffected Software
Mar 5, 2021
CVE Published
12:00 AM
Mar 7, 2021
CVE Published
via MITRE·04:03 AM
Data Sourced
via MITRE·04:03 AM
Description
Data Sourced
via NVD·05:15 AM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:54 PM
Description
Apr 28, 2025
Data Sourced
via Ubuntu·04:24 AM
RemedyDescriptionSeverityAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2021-27364?

The severity of CVE-2021-27364 is high, impacting data confidentiality and system availability.

2

How do I fix CVE-2021-27364?

To fix CVE-2021-27364, update the Linux kernel to the specified remedied versions provided by your distribution.

3

Which Linux kernel versions are affected by CVE-2021-27364?

CVE-2021-27364 affects multiple Linux kernel versions, notably those prior to the remedied versions listed in the security advisories.

4

What systems are vulnerable to CVE-2021-27364?

Systems running affected versions of the Linux kernel, including specific releases from Red Hat and Debian, are vulnerable to CVE-2021-27364.

5

What type of vulnerability is CVE-2021-27364?

CVE-2021-27364 is an out-of-bounds read vulnerability in the Linux kernel that can lead to unauthorized data access or crashes.

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