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.

CVSS v3 7.5 HIGH

7.5^/10

CVSS v3 : HIGH

Vector :

Exploitability : 3.9 / Impact : 3.6

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required NONE

User Interaction NONE

Confidentiality Impact NONE

Integrity Impact NONE

Availability Impact HIGH

Scope UNCHANGED

References

Link	Resource
https://github.com/gomarkdown/markdown/commit/759bbc3e32073c3bc4e25969c132fc520eda2778	Patch
https://github.com/gomarkdown/markdown/security/advisories/GHSA-77fj-vx54-gvh7	Exploit Vendor Advisory
https://github.com/gomarkdown/markdown/security/advisories/GHSA-77fj-vx54-gvh7	Exploit Vendor Advisory

Configurations

Configuration 1 (hide)

cpe:2.3:a:gomarkdown:markdown:*:*:*:*:*:go:*:*

History

26 Oct 2026, 21:10

Type	Values Removed	Values Added
Summary		(es) El paquete “github.com/gomarkdown/markdown” es una biblioteca Go para analizar texto Markdown y renderizar como HTML. Procesar una entrada malformada que contiene un carácter < que no es seguido por un carácter > en ninguna parte del texto restante con un SmartypantsRenderer conducirá a una lectura fuera de límites o a un pánico. Esta vulnerabilidad se corrige con el commit 759bbc3e32073c3bc4e25969c132fc520eda2778.

Information

Published : 2026-04-21 20:17

Updated : 2026-10-26 21:10

NVD link : CVE-2026-40890

Mitre link : CVE-2026-40890

CVE.ORG link : CVE-2026-40890

JSON object : View

Products Affected

gomarkdown

markdown

CWE

CWE-125

Out-of-bounds Read

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