CVE intelligence

CVE-2026-40890

Vulnerability intelligence

Published Apr 21, 2026Sources checked Nov 12, 2026

7.5HIGHCVSS out of 10

What this means

Review the available evidence

CVE-2026-40890 and is rated High severity with a CVSS score of 7.5. 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

1.22.3-21

CISA KEVNot listedBased on the latest collected catalog

EPSS0.3%Estimated 30-day exploitation probability

Ransomware useNot markedCISA KEV ransomware field

Threat actors0Source-linked actor relationships

Overview

What is CVE-2026-40890?

The package `github.com/gomarkdown/markdown` is a Go library for parsing Markdown text and rendering as HTML. Processing a malformed input containing a < character that is not followed by a > character anywhere in the remaining text with a SmartypantsRenderer will lead to Out of Bounds read or a panic.

This vulnerability is fixed with commit 759bbc3e32073c3bc4e25969c132fc520eda2778.

Source: NVD