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

No history.

Information

Published : 2026-04-21 20:17

Updated : 2026-06-17 10:45

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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