CVE intelligence

CVE-2026-18238

Vulnerability intelligence

Published Sep 5, 2026Sources checked Oct 28, 2026

5.0MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-18238 and is rated Medium severity with a CVSS score of 5.0. 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 15, 2026

See the Microsoft Security Update Guide for the update that applies to your product.

Vendor-listed releases

1.10.7-1

CISA KEVNot listedBased on the latest collected catalog

EPSS0.2%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-18238?

The rpcap client code that processes a RPCAP_MSG_PACKET message received from the server incorrectly validates its headers. A malicious server can send a crafted message and cause the client to treat up to 20 bytes of the client process memory beyond the end of the buffer as if it was a part of the captured packet.

Source: NVD