Description
In the Linux kernel, the following vulnerability has been resolved:

netfilter: nfnetlink_queue: hold nfnl mutex in event notifier

We must serialize the release notifier and the config netlink function.
A concurrent thread can issue close() which can call the release function
while unrelated socket processes UNBIND request for same portid:

Oops: general protection fault, [..]
RIP: 0010:__instance_destroy+0x60/0x210 [nfnetlink_queue]
Call Trace:
nfqnl_recv_config+0x9b0/0xdc0 [nfnetlink_queue]
nfnetlink_rcv_msg+0x7c2/0xeb0
? __pfx_nfnetlink_rcv_msg+0x10/0x10

After this, parallel UNBIND and URELEASE events are impossible.

This change isn't nice, but its the shortest fix given instances
are not refcounted and the nfnetlink config callback drops the
rcu read lock early due to need for sleeping allocations.
Published: 2026-10-18
Score: n/a
EPSS: n/a
KEV: No
Impact: Denial of Service via kernel crash
Action: Update Kernel
AI Analysis

Impact

A concurrency bug in the Linux kernel’s nfnetlink_queue subsystem allows a thread that closes a netlink socket to trigger the release function while another thread processes an UNBIND request for the same port identifier. This race condition causes a general protection fault in the nfnetlink_queue module, leading to a kernel panic and denial of service on the affected host.

Affected Systems

The flaw resides in the Linux kernel’s netfilter nfnetlink_queue implementation. Any kernel build that includes this subsystem is potentially vulnerable; specific affected kernel versions are not listed in the advisory.

Risk and Exploitability

The vulnerability is triggered by concurrent netlink operations and likely requires a privileged user to create the offending socket interactions, though this requirement is inferred from the need to open and close privileged netlink descriptors. No EPSS score or KEV listing is available, yet the impact is a kernel crash, which represents a critical failure mode. The lack of a public exploitation record suggests the risk is moderate until an exploit is discovered, but the severity of a kernel DoS warrants prompt action.

Generated by OpenCVE AI on October 18, 2026 at 22:37 UTC.

Remediation

No solution or workaround provided in the CVE record.

OpenCVE Recommended Actions

  • Upgrade the Linux kernel to a release incorporating the nfnetlink_queue mutex fix
  • If the system does not rely on nfnetlink_queue services, disable the nfnetlink_queue netlink module or netfilter queue support as a temporary measure
  • Monitor system logs for nfnetlink_queue related Oops events and consider restricting netfilter traffic to reduce the risk of exploitation

Generated by OpenCVE AI on October 18, 2026 at 22:37 UTC.

Tracking

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Advisories

No advisories yet.

History

Sun, 18 Oct 2026 23:00:00 +0000

Type Values Removed Values Added
Weaknesses CWE-362

Sun, 18 Oct 2026 15:30:00 +0000

Type Values Removed Values Added
Description In the Linux kernel, the following vulnerability has been resolved: netfilter: nfnetlink_queue: hold nfnl mutex in event notifier We must serialize the release notifier and the config netlink function. A concurrent thread can issue close() which can call the release function while unrelated socket processes UNBIND request for same portid: Oops: general protection fault, [..] RIP: 0010:__instance_destroy+0x60/0x210 [nfnetlink_queue] Call Trace: nfqnl_recv_config+0x9b0/0xdc0 [nfnetlink_queue] nfnetlink_rcv_msg+0x7c2/0xeb0 ? __pfx_nfnetlink_rcv_msg+0x10/0x10 After this, parallel UNBIND and URELEASE events are impossible. This change isn't nice, but its the shortest fix given instances are not refcounted and the nfnetlink config callback drops the rcu read lock early due to need for sleeping allocations.
Title netfilter: nfnetlink_queue: hold nfnl mutex in event notifier
First Time appeared Linux
Linux linux Kernel
CPEs cpe:2.3:o:linux:linux_kernel:*:*:*:*:*:*:*:*
Vendors & Products Linux
Linux linux Kernel
References

Subscriptions

Linux Linux Kernel
cve-icon MITRE

Status: PUBLISHED

Assigner: Linux

Published:

Updated: 2026-10-18T15:19:45.566Z

Reserved: 2026-09-25T10:25:14.360Z

Link: CVE-2026-98624

cve-icon Vulnrichment

No data.

cve-icon NVD

Status : Received

Published: 2026-10-18T16:17:15.393

Modified: 2026-10-18T16:17:15.393

Link: CVE-2026-98624

cve-icon Redhat

No data.

cve-icon OpenCVE Enrichment

Updated: 2026-10-18T22:45:04Z

Weaknesses
  • CWE-362

    Concurrent Execution using Shared Resource with Improper Synchronization ('Race Condition')