CVE-2022-25636: High severity Linux Linux kernel vulnerability

Published Feb 22, 2022
·
Updated

An out-of-bounds (OOB) memory access flaw was found in nftfwddupnetdevoffload in net/netfilter/nfdupnetdev.c in netfilter subcomponent in the Linux kernel due to a heap out of bounds write problem. In this flaw, an attacker with a user account on the system to gain access to out-of-bounds memory leads to a system crash or a privilege escalation threat.

Reference:

https://git.kernel.org/pub/scm/linux/kernel/git/netfilter/nf.git/commit/?id=b1a5983f56e371046dcf164f90bfaf704d2b89f6 https://www.openwall.com/lists/oss-security/2022/02/21/2

Other sources

An out-of-bounds (OOB) memory access flaw was found in nftfwddupnetdevoffload in net/netfilter/nfdupnetdev.c in the netfilter subcomponent in the Linux kernel due to a heap out-of-bounds write problem. This flaw allows a local attacker with a user account on the system to gain access to out-of-bounds memory, leading to a system crash or a privilege escalation threat.

net/netfilter/nfdupnetdev.c in the Linux kernel 5.4 through 5.6.10 allows local users to gain privileges because of a heap out-of-bounds write. This is related to nftablesoffload.

Affected Software

29 affected componentsFixes available
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-rt<0:4.18.0-305.45.1.rt7.117.el8_4
0:4.18.0-305.45.1.rt7.117.el8_4
redhat/kernel<0:4.18.0-305.45.1.el8_4
0:4.18.0-305.45.1.el8_4
Linux Linux kernel>=5.4<5.4.182
Linux Linux kernel>=5.5<5.10.103
Linux Linux kernel>=5.11<5.15.26
Linux Linux kernel>=5.16<5.16.12
Debian Debian Linux=11.0
NetApp H300e
NetApp H300s
NetApp H410c
NetApp H410s
NetApp H500e
NetApp H500s
NetApp H700e
NetApp H700s
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 Baseboard Management Controller H300e
NetApp Baseboard Management Controller H300s
NetApp Baseboard Management Controller H410c
NetApp Baseboard Management Controller H410s
NetApp Baseboard Management Controller H500e
NetApp Baseboard Management Controller H500s
NetApp Baseboard Management Controller H700e
NetApp Baseboard Management Controller H700s
debian/linux
5.10.223-15.10.234-16.1.129-16.1.135-16.12.25-1

Remediation

Information

The mitigation for the Red Hat Enterprise Linux 8 is to disable for unprivileged user possibilities of running unshare(CLONE_NEWUSER) or unshare(CLONE_NEWNET) that could be done with the next command: echo 0 > /proc/sys/user/max_user_namespaces For making this change in configuration permanent. Note: User namespaces are used primarily for Linux containers. If containers are in use, this requirement is not applicable. Configure RHEL 8 to disable the use of user namespaces by adding the following line to a file in the "/etc/sysctl.d/" directory: user.max_user_namespaces = 0 The system configuration files need to be reloaded for the changes to take effect. To reload the contents of the files, run the following command: $ sudo sysctl --system The other mitigation for containers, if without disabling user namespaces, is blocking the pertinent syscalls in a seccomp policy file. For more information about seccomp, please read: https://www.openshift.com/blog/seccomp-for-fun-and-profit

Mitigation

Disable unprivileged user namespaces to restrict access to privileged users (have CAP_NET_ADMIN) via the kernel.unprivileged_userns_clone sysctl: $ sudo sysctl kernel.unprivileged_userns_clone=0

Event History

Feb 22, 2022
CVE Published
12:00 AM
CVE Published
via MITRE·01:41 AM
Data Sourced
via MITRE·01:41 AM
Description
Data Sourced
via Red Hat·07:11 AM
DescriptionSeverityAffected Software
Jan 12, 2024
Data Sourced
via Launchpad·12:07 AM
Description
May 2, 2025
Data Sourced
via Ubuntu·04:19 AM
RemedyDescriptionSeverityAffected Software
May 6, 2025
Data Sourced
via Debian·04:20 AM
DescriptionAffected Software

Parent advisories

This vulnerability appears in the following advisories.

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Frequently Asked Questions

1

What is the severity of CVE-2022-25636?

CVE-2022-25636 has been classified as a high severity vulnerability due to the potential for out-of-bounds memory access and exploitation.

2

How do I fix CVE-2022-25636?

To fix CVE-2022-25636, users should update their kernel to the patched versions provided by their respective distributions, such as kernel-rt or the standard kernel from Red Hat and Debian.

3

What types of systems are affected by CVE-2022-25636?

CVE-2022-25636 affects Linux kernel versions that are susceptible to the identified out-of-bounds memory access issue, particularly those versions between 5.4 and 5.16.

4

Can CVE-2022-25636 be exploited remotely?

CVE-2022-25636 requires an attacker to have local user access to exploit the vulnerability, thus making remote exploitation less likely.

5

What can attackers achieve by exploiting CVE-2022-25636?

Exploiting CVE-2022-25636 may allow attackers to corrupt memory, leading to potential denial of service or gaining control over the affected systems.

Contact

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