CVE-2020-10711: Null Pointer Dereference

Published Apr 17, 2020
·
Updated

A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem in versions before 5.7. This flaw occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmapnetlblimport' routine. While processing the CIPSO restricted bitmap tag in the 'cipsov4parsetagrbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the system kernel, resulting in a denial of service.

Other sources

A NULL pointer dereference flaw was found in the Linux kernel's SELinux subsystem. This flaw occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into the SELinux extensible bitmap via the' ebitmapnetlblimport' routine. While processing the CIPSO restricted bitmap tag in the 'cipsov4parsetagrbm' routine, it sets the security attribute to indicate that the category bitmap is present, even if it has not been allocated. This issue leads to a NULL pointer dereference issue while importing the same category bitmap into SELinux. This flaw allows a remote network user to crash the system kernel, resulting in a denial of service.

A NULL pointer dereference issue was found in the Linux kernel's SELinux subsystem. It occurs while importing the Commercial IP Security Option (CIPSO) protocol's category bitmap into SELinux's extensible bitmap via 'ebitmapnetlblimport' routine. While parsing the CIPSO restricted bitmap tag in 'cipsov4parsetagrbm' routine, it sets the security attribute to indicate that category bitmap is present, even if it has not been allocated. This leads to the said NULL pointer dereference issue while importing the same category bitmap into SELinux. A remote network user could use this flaw to crash the system kernel resulting in DoS scenario.

This issue was introduced by upstream commit: -> https://git.kernel.org/linus/4b8feff251da3d7058b5779e21b33a85c686b974 netlabel: fix the horribly broken catmap functions

Upstream patch: --------------- -> https://lore.kernel.org/netdev/07d99ae197bfdb2964931201db67b6cd0b38db5b.1589276729.git.pabeni@redhat.com/T/#u

Reference: ---------- -> https://www.openwall.com/lists/oss-security/2020/05/12/2

— Red Hat

Affected Software

36 affected componentsFixes available
redhat/kernel<0:2.6.32-754.29.2.el6
0:2.6.32-754.29.2.el6
redhat/kernel-rt<0:3.10.0-1127.8.2.rt56.1103.el7
0:3.10.0-1127.8.2.rt56.1103.el7
redhat/kernel<0:3.10.0-1127.8.2.el7
0:3.10.0-1127.8.2.el7
redhat/kernel-alt<0:4.14.0-115.21.2.el7a
0:4.14.0-115.21.2.el7a
redhat/kernel<0:3.10.0-327.88.1.el7
0:3.10.0-327.88.1.el7
redhat/kernel<0:3.10.0-514.76.1.el7
0:3.10.0-514.76.1.el7
redhat/kernel<0:3.10.0-693.67.1.el7
0:3.10.0-693.67.1.el7
redhat/kernel<0:3.10.0-957.54.1.el7
0:3.10.0-957.54.1.el7
redhat/kernel<0:3.10.0-1062.26.1.el7
0:3.10.0-1062.26.1.el7
redhat/kernel-rt<0:4.18.0-193.1.2.rt13.53.el8_2
0:4.18.0-193.1.2.rt13.53.el8_2
redhat/kernel<0:4.18.0-193.1.2.el8_2
0:4.18.0-193.1.2.el8_2
redhat/kernel<0:4.18.0-80.23.2.el8_0
0:4.18.0-80.23.2.el8_0
redhat/kernel<0:4.18.0-147.13.2.el8_1
0:4.18.0-147.13.2.el8_1
redhat/kernel-rt<1:3.10.0-693.67.1.rt56.665.el6
1:3.10.0-693.67.1.rt56.665.el6
Linux Linux kernel<5.7
redhat 3scale=2.0
redhat Openstack=13
redhat Virtualization Host=4.0
redhat Enterprise Linux=6.0
redhat Enterprise Linux=7.0
redhat Enterprise Linux=8.0
redhat Enterprise Linux Aus=7.4
redhat Enterprise Linux Server Tus=7.4
redhat Messaging Realtime Grid=2.0
Debian Debian Linux=8.0
Debian Debian Linux=9.0
Debian Debian Linux=10.0
openSUSE Leap=15.1
openSUSE Leap=15.2
Canonical Ubuntu Linux=14.04
Canonical Ubuntu Linux=16.04
Canonical Ubuntu Linux=18.04
Canonical Ubuntu Linux=19.10
Canonical Ubuntu Linux=20.04
redhat/kernel<5.7
5.7
debian/linux
5.10.223-15.10.262-16.1.176-16.1.180-16.12.94-16.12.101-17.1.7-17.1.8-1

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

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

    Fixed in 0:2.6.32-754.29.2.el6
  2. Upgrade

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

    Fixed in 0:3.10.0-1127.8.2.rt56.1103.el7
  3. Upgrade

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

    Fixed in 0:3.10.0-1127.8.2.el7
  4. Upgrade

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

    Fixed in 0:4.14.0-115.21.2.el7a
  5. Upgrade

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

    Fixed in 0:3.10.0-327.88.1.el7
  6. Upgrade

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

    Fixed in 0:3.10.0-514.76.1.el7
  7. Upgrade

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

    Fixed in 0:3.10.0-693.67.1.el7
  8. Upgrade

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

    Fixed in 0:3.10.0-957.54.1.el7
  9. Upgrade

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

    Fixed in 0:3.10.0-1062.26.1.el7
  10. Upgrade

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

    Fixed in 0:4.18.0-193.1.2.rt13.53.el8_2
  11. Upgrade

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

    Fixed in 0:4.18.0-193.1.2.el8_2
  12. Upgrade

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

    Fixed in 0:4.18.0-80.23.2.el8_0
  13. Upgrade

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

    Fixed in 0:4.18.0-147.13.2.el8_1
  14. Upgrade

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

    Fixed in 1:3.10.0-693.67.1.rt56.665.el6
  15. Upgrade

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

    Fixed in 5.7
  16. Upgrade

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

    Fixed in 5.10.223-1Fixed in 5.10.262-1Fixed in 6.1.176-1Fixed in 6.1.180-1Fixed in 6.12.94-1Fixed in 6.12.101-1Fixed in 7.1.7-1Fixed in 7.1.8-1

Event History

Apr 17, 2020
Data Sourced
via Red Hat·06:32 AM
DescriptionSeverityAffected Software
May 12, 2020
CVE Published
12:00 PM
May 22, 2020
CVE Published
via MITRE·02:09 PM
Data Sourced
via MITRE·02:09 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·03:15 PM
RemedyDescriptionSeverityWeaknessAffected Software
Jan 11, 2024
Data Sourced
via Launchpad·11:36 PM
Description
Aug 12, 2026
Data Sourced
via Debian·04:23 PM
DescriptionAffected Software
Aug 14, 2026
Data Sourced
via Ubuntu·04:23 PM
RemedyDescriptionSeverityAffected Software

Parent advisories

This vulnerability appears in the following advisories.

Free Weekly Intel

Don't miss critical vulnerabilities

Join thousands of security professionals who receive our weekly digest of trending CVEs, zero-days, and exploited vulnerabilities.

No spam. Unsubscribe anytime.

Frequently Asked Questions

1

What is the severity of CVE-2020-10711?

CVE-2020-10711 has been classified as a moderate vulnerability due to the NULL pointer dereference issue in the Linux kernel's SELinux subsystem.

2

How do I fix CVE-2020-10711?

To fix CVE-2020-10711, upgrade your Linux kernel to version 5.7 or later, or apply the specific patches available for affected versions.

3

Which Linux kernel versions are affected by CVE-2020-10711?

CVE-2020-10711 affects Linux kernel versions prior to 5.7.

4

What systems are impacted by CVE-2020-10711?

Systems running affected versions of the Linux kernel, including various distributions like Red Hat and Debian, are impacted by CVE-2020-10711.

5

Is CVE-2020-10711 a remote code execution vulnerability?

CVE-2020-10711 is not a remote code execution vulnerability; it involves a local NULL pointer dereference which can lead to a denial of service.

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