Kernel: refcount leak in ctnetlink_create_conntrack() (CVE-2023-7192)

Why this deserves its current priority

CVSS is 5.5. The current sources do not mark it as known exploited. Treat this as a source-backed prioritization signal, not a statement about your environment.

Analysis status

Analysis pending evidence review

Factual feed record only; HOL analysis is not approved for indexing. Read the methodology.

Affected scope and exposure questions

The current feed maps Red Hat/kernel (generic), Red Hat/kernel-rt (generic). Check affected ranges and fixed versions before updating.

Mapped affected packages and fixed versions
Package	Affected range	Fixed version
Red Hat/kernelgeneric	*	Not reported
Red Hat/kernel-rtgeneric	*	Not reported

Recommended response

Check inventory. Check lockfiles and deployed manifests for Red Hat/kernel, Red Hat/kernel-rt.
Review the reported fix. Source-reported 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 ~~~

Evidence timeline and material changes

Published upstream
Jan 2, 2024
Evidence: source:cvelist:source_dates:source-dates:record
Source modified
Nov 5, 2026
Evidence: source:cvelist:source_dates:source-dates:record
First seen by HOL
Nov 5, 2026

Sources and claim methodology

Upstream source 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.

Quoted source text, attributed separately from HOL analysis.

Kernel: refcount leak in ctnetlink_create_conntrack()CVE-2023-7192