high
7.8
CWE
416
Advisory Published
CVE Published
Updated

CVE-2021-4028: Use After Free

First published: Mon Oct 04 2021(Updated: )

A flaw in the Linux kernel's implementation of RDMA communications manager listener code allowed an attacker with local access to setup a socket to listen on a high port allowing for a list element to be used after free. Given the ability to execute code, a local attacker could leverage this use-after-free to crash the system or possibly escalate privileges on the system.

Credit: secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
redhat/kernel-rt<0:3.10.0-1160.62.1.rt56.1203.el7
0:3.10.0-1160.62.1.rt56.1203.el7
redhat/kernel<0:3.10.0-1160.62.1.el7
0:3.10.0-1160.62.1.el7
redhat/kernel<0:3.10.0-514.101.1.el7
0:3.10.0-514.101.1.el7
redhat/kernel<0:3.10.0-693.100.1.el7
0:3.10.0-693.100.1.el7
redhat/kernel<0:3.10.0-957.94.1.el7
0:3.10.0-957.94.1.el7
redhat/kernel<0:3.10.0-1062.66.1.el7
0:3.10.0-1062.66.1.el7
redhat/kernel-rt<0:4.18.0-348.23.1.rt7.153.el8_5
0:4.18.0-348.23.1.rt7.153.el8_5
redhat/kernel<0:4.18.0-348.23.1.el8_5
0:4.18.0-348.23.1.el8_5
redhat/kernel<0:4.18.0-147.64.1.el8_1
0:4.18.0-147.64.1.el8_1
redhat/kernel-rt<0:4.18.0-193.75.1.rt13.125.el8_2
0:4.18.0-193.75.1.rt13.125.el8_2
redhat/kernel<0:4.18.0-193.75.1.el8_2
0:4.18.0-193.75.1.el8_2
redhat/kernel-rt<0:4.18.0-305.40.1.rt7.112.el8_4
0:4.18.0-305.40.1.rt7.112.el8_4
redhat/kernel<0:4.18.0-305.40.1.el8_4
0:4.18.0-305.40.1.el8_4
redhat/redhat-virtualization-host<0:4.3.22-20220330.1.el7_9
0:4.3.22-20220330.1.el7_9
redhat/kernel<5.15
5.15
Linux Kernel>=5.10<5.10.71
Linux Kernel>=5.11<5.14.10
SUSE Linux Enterprise Server=15.0-sp3
SUSE Linux Enterprise Server=15.0-sp4

Remedy

https://bugzilla.suse.com/show_bug.cgi?id=1193167#c0

Remedy

https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=bc0bdc5afaa74

Remedy

https://lkml.org/lkml/2021/10/4/697

Remedy

Mitigation for this issue is either not available or the currently available options does not meet the Red Hat Product Security criteria comprising ease of use and deployment, applicability to widespread installation base or stability.

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is CVE-2021-4028?

    CVE-2021-4028 is a vulnerability in the Linux kernel's implementation of RDMA communications manager listener code.

  • How severe is CVE-2021-4028?

    CVE-2021-4028 has a severity value of 7, which is considered high.

  • What is the affected software for CVE-2021-4028?

    The affected software includes Red Hat kernel versions up to 5.15, kernel-rt versions up to 3.10.0-1160.62.1.rt56.1203.el7, and SUSE Linux Enterprise versions 15.0-sp3 and 15.0-sp4.

  • How do I fix CVE-2021-4028?

    To fix CVE-2021-4028, you need to update your Linux kernel to a version that includes the necessary patches. Refer to the vendor's security advisory for the specific kernel versions that address the vulnerability.

  • Where can I find more information about CVE-2021-4028?

    You can find more information about CVE-2021-4028 in the Red Hat bugzilla and SUSE bugzilla links provided, as well as the Red Hat security advisory.

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