CVE intelligence

CVE-2026-86137

Vulnerability intelligence

Published Sep 5, 2026Sources checked Oct 28, 2026

6.1MEDIUMCVSS out of 10

What this means

Review the available evidence

CVE-2026-86137 and is rated Medium severity with a CVSS score of 6.1. 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 23, 2026

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

Vendor-listed releases

2.11.5-11

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-2026-86137?

In libxml2 before 2.15.4, xmlFAParsePosCharGroup has an out-of-bounds read, aka an out-of-bounds read in the NXT macro in xmlregexp.

Source: NVD