CVE-2021-27365: Buffer Overflow

Published Feb 18, 2021
·
Updated

A flaw was found in the Linux kernel. A heap buffer overflow in the iSCSI subsystem is triggered by setting an iSCSI string attribute to a value larger than one page and then trying to read it. The highest threat from this vulnerability is to data confidentiality and integrity as well as system availability.

Other sources

A heap buffer overflow vulnerability was found in the linux kernel in the iSCSI subsystem. The vulnerability is triggered by setting an iSCSI string attribute to a value larger than one page, and then trying to read it.

— Red Hat

An issue was discovered in the Linux kernel through 5.11.3. Certain iSCSI data structures do not have appropriate length constraints or checks, and can exceed the PAGESIZE value. An unprivileged user can send a Netlink message that is associated with iSCSI, and has a length up to the maximum length of a Netlink message.

Affected Software

30 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
Oracle Tekelec Platform Distribution>=7.4.0<=7.7.1
All of the following
NetApp Solidfire Baseboard Management Controller Firmware
NetApp Solidfire Baseboard Management Controller
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

    Add the following line to /etc/modprobe.d/disable-libiscsi.conf to prevent the libiscsi kernel module from auto-loading: install libiscsi /bin/true. (This mitigation may not be suitable if the system requires iSCSI.)

    Linux kernel module loader (modprobe) for libiscsi install libiscsi /bin/true = Disable auto-loading of libiscsi
  17. Operational

    If the libiscsi modules are loaded, restart the system after applying the mitigation/config change so the modules are no longer in use.

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·04:22 AM
Data Sourced
via MITRE·04:22 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·04:25 AM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2021-27365?

CVE-2021-27365 has a high severity due to its potential impact on data confidentiality and integrity.

2

How do I fix CVE-2021-27365?

To fix CVE-2021-27365, upgrade your kernel to the latest available version provided by your distribution.

3

What are the affected operating systems for CVE-2021-27365?

CVE-2021-27365 affects various versions of the Linux kernel across Red Hat, Debian, and Oracle systems.

4

What types of systems are primarily impacted by CVE-2021-27365?

CVE-2021-27365 primarily impacts systems using the iSCSI subsystem in the Linux kernel.

5

Is CVE-2021-27365 exploitable remotely?

Yes, CVE-2021-27365 can potentially be exploited remotely if the iSCSI service is exposed.

Company

Resources

Contact

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