CVE intelligence

CVE-2026-31509

Vulnerability intelligence

Published Apr 22, 2026Sources checked Nov 12, 2026

5.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-31509 and is rated Medium severity with a CVSS score of 5.5. It is not in the current CISA KEV record we collected. That does not prove exploitation has not occurred.

What to do next

Remediation and response

Microsoft Security Response Center guidance

Vendor revision: Sep 25, 2026

CBL-Mariner Releases Release Notes

Vendor-listed releases

6.6.134.1-2

CISA KEVNot listedBased on the latest collected catalog

EPSS0.1%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-31509?

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

nfc: nci: fix circular locking dependency in nci_close_device

nci_close_device() flushes rx_wq and tx_wq while holding req_lock. This causes a circular locking dependency because nci_rx_work() running on rx_wq can end up taking req_lock too:

nci_rx_work -> nci_rx_data_packet -> nci_data_exchange_complete -> __sk_destruct -> rawsock_destruct -> nfc_deactivate_target -> nci_deactivate_target -> nci_request -> mutex_lock(&ndev->req_lock)

Move the flush of rx_wq after req_lock has been released. This should safe (I think) because NCI_UP has already been cleared and the transport is closed, so the work will see it and return -ENETDOWN.

NIPA has been hitting this running the nci selftest with a debug kernel on roughly 4% of the runs.

Source: NVD