CVE intelligence

CVE-2026-43491

Vulnerability intelligence

Published May 19, 2026Sources checked Nov 13, 2026

5.5MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-43491 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: Jun 9, 2026

CBL-Mariner Releases

Vendor-listed releases

6.6.141.1-1

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-2026-43491?

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

net: qrtr: ns: Limit the maximum server registration per node

Current code does no bound checking on the number of servers added per node. A malicious client can flood NEW_SERVER messages and exhaust memory.

Fix this issue by limiting the maximum number of server registrations to 256 per node. If the NEW_SERVER message is received for an old port, then don't restrict it as it will get replaced.

While at it, also rate limit the error messages in the failure path of qrtr_ns_worker().

Note that the limit of 256 is chosen based on the current platform requirements. If requirement changes in the future, this limit can be increased.

Source: NVD