CVE-2026-40890 (GCVE-0-2026-40890)

Vulnerability from cvelistv5 – Published: 2026-04-21 19:51 – Updated: 2026-04-21 20:36
VLAI
Title
github.com/gomarkdown/markdown: Out-of-bounds Read in SmartypantsRenderer
Summary
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.
Severity
7.5 (High)
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
SSVC
Exploitation: poc Automatable: yes Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-04-21 20:16 UTC
CWE
Assigner
GitHub_M CNA under the mitre root
CNA scorecard C 72/100 over 8038 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
gomarkdown markdown Affected: < 759bbc3e32073c3bc4e25969c132fc520eda2778
guessed Create a notification for this product.
Show details on NVD website
To clipboard 

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