medium
6.8
CWE
362 416
Advisory Published
CVE Published
Updated

CVE-2021-4203: Race Condition

First published: Wed Sep 29 2021(Updated: )

A use-after-free read flaw was found in sock_getsockopt() in net/core/sock.c due to SO_PEERCRED and SO_PEERGROUPS race with listen() (and connect()) in the Linux kernel. In this flaw, an attacker with a user privilege may lead to a system crash or a leak of internal kernel information. In this, if the creds are replaced and freed at the wrong time, a use-after-free read occurs. References: <a href="https://lore.kernel.org/netdev/20210929225750.2548112-1-eric.dumazet@gmail.com/T/">https://lore.kernel.org/netdev/20210929225750.2548112-1-eric.dumazet@gmail.com/T/</a> <a href="https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=35306eb23814">https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=35306eb23814</a> <a href="https://bugs.chromium.org/p/project-zero/issues/detail?id=2230&amp;can=7&amp;q=modified-after%3Atoday-30&amp;sort=-modified&amp;colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified%20Cve&amp;cells=tiles&amp;redir=1">https://bugs.chromium.org/p/project-zero/issues/detail?id=2230&amp;can=7&amp;q=modified-after%3Atoday-30&amp;sort=-modified&amp;colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified%20Cve&amp;cells=tiles&amp;redir=1</a>

Credit: secalert@redhat.com

Affected SoftwareAffected VersionHow to fix
redhat/kernel-rt<0:4.18.0-372.9.1.rt7.166.el8
0:4.18.0-372.9.1.rt7.166.el8
redhat/kernel<0:4.18.0-372.9.1.el8
0:4.18.0-372.9.1.el8
redhat/kernel-rt<0:4.18.0-305.57.1.rt7.129.el8_4
0:4.18.0-305.57.1.rt7.129.el8_4
redhat/kernel<0:4.18.0-305.57.1.el8_4
0:4.18.0-305.57.1.el8_4
redhat/kernel<5.15
5.15
Linux Kernel<5.15
Linux Kernel=5.15
Linux Kernel=5.15-rc1
Linux Kernel=5.15-rc2
Linux Kernel=5.15-rc3
NetApp Active IQ Unified Manager for VMware vSphere
NetApp E-Series SANtricity OS Controller>=11.0.0<=11.70.2
NetApp Management Services for Element Software
NetApp SolidFire & HCI Management Node
NetApp SolidFire & HCI Storage Node
All of
NetApp HCI Bootstrap OS
NetApp HCI Compute Node
All of
NetApp AFF A700s Firmware
NetApp A700
All of
NetApp H300S Firmware
NetApp H300S Firmware
All of
NetApp H500e Firmware
NetApp H500e Firmware
All of
NetApp H700S
NetApp H700S
All of
NetApp H410S
NetApp H410S Firmware
All of
NetApp H410C
NetApp H410C Firmware
Oracle Communications Cloud Native Core Binding Support Function=22.1.3
Oracle Communications Cloud Native Core Network Exposure Function=22.1.1
Oracle Communications Cloud Native Core Policy=22.2.0
NetApp HCI Bootstrap OS
NetApp HCI Compute Node
NetApp AFF A700s Firmware
NetApp A700
NetApp H300S Firmware
NetApp H300S Firmware
NetApp H500e Firmware
NetApp H500e Firmware
NetApp H700S
NetApp H700S
NetApp H410S
NetApp H410S Firmware
NetApp H410C
NetApp H410C Firmware
debian/linux
5.10.223-1
5.10.234-1
6.1.129-1
6.1.128-1
6.12.20-1
6.12.21-1

Remedy

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

Remedy

https://bugs.chromium.org/p/project-zero/issues/detail?id=2230&can=7&q=modified-after%3Atoday-30&sort=-modified&colspec=ID%20Type%20Status%20Priority%20Milestone%20Owner%20Summary%20Modified%20Cve&cells=tiles&redir=1

Remedy

https://bugzilla.redhat.com/show_bug.cgi?id=2036934

Remedy

https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=35306eb23814

Remedy

https://lore.kernel.org/netdev/20210929225750.2548112-1-eric.dumazet@gmail.com/T/

Remedy

https://www.oracle.com/security-alerts/cpujul2022.html

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Reference Links

Parent vulnerabilities

(Appears in the following advisories)

Frequently Asked Questions

  • What is the severity of CVE-2021-4203?

    CVE-2021-4203 is rated as having a high severity level due to its potential to cause system crashes or leak internal kernel information.

  • How do I fix CVE-2021-4203?

    To remediate CVE-2021-4203, upgrade to the recommended kernel versions as specified in security advisories or vendor documentation.

  • What type of vulnerability is CVE-2021-4203?

    CVE-2021-4203 is a use-after-free read flaw in the Linux kernel that can be exploited due to improper handling of socket options.

  • Who is affected by CVE-2021-4203?

    Users of vulnerable versions of the Linux kernel, specifically those using certain Red Hat and Debian kernels, are at risk from CVE-2021-4203.

  • What conditions are necessary for CVE-2021-4203 to be exploited?

    An attacker must have user privileges on the system to exploit CVE-2021-4203, allowing them to trigger the vulnerability.

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