Kernel: refcount leak in ctnetlink_create_conntrack()

Description

A memory leak problem was found in ctnetlink_create_conntrack in net/netfilter/nf_conntrack_netlink.c in the Linux Kernel. This issue may allow a local attacker with CAP_NET_ADMIN privileges to cause a denial of service (DoS) attack due to a refcount overflow.

Scores

EPSS (exploitation in 30 days)

0.30% · top 77% of all CVEs (6 Nov 2026)

CISA SSVC

Exploitation: none · Automatable: no · Technical impact: partial

The list uses the assigner's score when there is one, then CISA's, then NVD's: Medium 5.5.

Weakness

• CWE-401: Missing Release of Memory after Effective Lifetime (opens in a new tab)All about CWE-401 and its CVEs

Affected products

• Red Hat · Red Hat Enterprise Linux 8.2 Advanced Update Support

  • unaffected 0:4.18.0-193.133.1.el8_2 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Telecommunications Update Service

  • unaffected 0:4.18.0-193.133.1.rt13.184.el8_2 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Telecommunications Update Service

  • unaffected 0:4.18.0-193.133.1.el8_2 – < *

• Red Hat · Red Hat Enterprise Linux 8.2 Update Services for SAP Solutions

  • unaffected 0:4.18.0-193.133.1.el8_2 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Advanced Mission Critical Update Support

  • unaffected 0:4.18.0-305.125.1.el8_4 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Telecommunications Update Service

  • unaffected 0:4.18.0-305.125.1.rt7.201.el8_4 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Telecommunications Update Service

  • unaffected 0:4.18.0-305.125.1.el8_4 – < *

• Red Hat · Red Hat Enterprise Linux 8.4 Update Services for SAP Solutions

  • unaffected 0:4.18.0-305.125.1.el8_4 – < *

• Red Hat · Red Hat Enterprise Linux 8.6 Extended Update Support

  • unaffected 0:4.18.0-372.95.1.el8_6 – < *

• Red Hat · Red Hat Enterprise Linux 8.8 Extended Update Support

  • unaffected 0:4.18.0-477.51.1.el8_8 – < *

• Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support

  • unaffected 0:5.14.0-70.93.2.el9_0 – < *

• Red Hat · Red Hat Enterprise Linux 9.0 Extended Update Support

  • unaffected 0:5.14.0-70.93.1.rt21.165.el9_0 – < *

• Red Hat · Red Hat Enterprise Linux 9.2 Extended Update Support

  • unaffected 0:5.14.0-284.52.1.el9_2 – < *

• Red Hat · Red Hat Enterprise Linux 9.2 Extended Update Support

  • unaffected 0:5.14.0-284.52.1.rt14.337.el9_2 – < *

• Red Hat · Red Hat Virtualization 4 for Red Hat Enterprise Linux 8

  • unaffected 0:4.18.0-372.95.1.el8_6 – < *

• Red Hat · Red Hat Enterprise Linux 6

  All versions: unknown

• Red Hat · Red Hat Enterprise Linux 7

  All versions: unknown

• Red Hat · Red Hat Enterprise Linux 7

  All versions: unknown

• Red Hat · Red Hat Enterprise Linux 8

  All versions: affected

• Red Hat · Red Hat Enterprise Linux 8

  All versions: affected

• Red Hat · Red Hat Enterprise Linux 9

  All versions: affected

• Red Hat · Red Hat Enterprise Linux 9

  All versions: affected

What to do

Workaround: Triggering this issue requires the ability to create user/net namespaces. On non-containerized deployments of Red Hat Enterprise Linux 8, you can disable user namespaces by setting user.max_user_namespaces to 0: # echo "user.max_user_namespaces=0" > /etc/sysctl.d/userns.conf # sysctl -p /etc/sysctl.d/userns.conf On containerized deployments, such as Red Hat OpenShift Container Platform, do not use this mitigation as the functionality is needed to be enabled. Alternatively, skip loading the affected netfilter module (i.e., nf_conntrack_netlink) onto the system until we have a fix available. This can be done by a blacklist mechanism which will ensure the driver is not loaded at boot time. ~~~ How do I blacklist a kernel module to prevent it from loading automatically? https://access.redhat.com/solutions/41278 ~~~

References (13)

• RHSA-2024:0723 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:0725 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1188 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1250 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1306 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1367 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1382 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:1404 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:2006 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• RHSA-2024:2008 (opens in a new tab)vendor-advisoryx_refsource_REDHATx_transferred
• https://access.redhat.com/security/cve/CVE-2023-7192 (opens in a new tab)vdb-entryx_refsource_REDHATx_transferred
• RHBZ#2256279 (opens in a new tab)issue-trackingx_refsource_REDHATx_transferred
• https://git.kernel.org/pub/scm/linux/kernel/git/netdev/net.git/commit/?id=ac4893980bbe79ce383daf9a0885666a30fe4c83 (opens in a new tab)x_transferred

Sources

The same CVE in the primary databases and aggregators, to check against.

• CVE.org record (opens in a new tab)
• CVE List JSON (GitHub) (opens in a new tab)
• NVD (opens in a new tab)
• FIRST EPSS (opens in a new tab)
• OSV.dev (opens in a new tab)
• GitHub Advisories (opens in a new tab)
• CIRCL Vulnerability-Lookup (opens in a new tab)

Badge for a README or a ticket

[![CVE-2023-7192](https://trackcve.app/badge/CVE-2023-7192.svg)](https://trackcve.app/cve/CVE-2023-7192)

Record last updated 5 Nov 2026, 11:38 UTC.