CVE-2026-40890
7.5 · HIGHOverview
CVE-2026-40890 is a high-severity vulnerability affecting gomarkdown markdown. It was published on April 21, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
Technical Description
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.
Remediation
Check the references section for vendor advisories and patches from gomarkdown. Update markdown to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| gomarkdown | markdown | >= 0, < 2026-04-10 | Affected |
Frequently Asked Questions
What is CVE-2026-40890?
CVE-2026-40890 is a high-severity vulnerability affecting gomarkdown markdown. It was published on April 21, 2026 and has a CVSS 3.1 base score of 7.5 (HIGH).
How severe is CVE-2026-40890?
This vulnerability has a CVSS 3.1 base score of 7.5, rated HIGH. It can be exploited remotely over the network. No authentication or special privileges are required for exploitation.
How do I fix or remediate CVE-2026-40890?
Check the references section for vendor advisories and patches from gomarkdown. Update markdown to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40890?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40890 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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