CVE-2026-8661

Medium

Description

Server-Side Request Forgery in the markdown_to_pdf action of Rapid7 InsightConnect Markdown Plugin on Linux in versions prior to 4.0.2 allows remote attackers to make arbitrary outbound HTTP requests via unsanitized resource-loading HTML elements (img/src, CSS url(), @import) embedded in Markdown input. The initial fix in 4.0.0 disabled JavaScript but did not neutralize resource-loading vectors. Resolved in 4.0.2 by sanitizing HTML with an allowlist of tags, attributes, and URL schemes.

SeverityMedium

CVSS4.8

Exploit probability—

ProductInsightConnect Markdown Plugin

PublishedJun 26, 2026

First seenJun 26, 2026

Weakness typeCWE-79Cross-site scripting (XSS)CWE-918Server-side request forgery (SSRF)

How to fix

Update

Rapid7 InsightConnect Markdown Plugin4.0.2 or later

Patches

Vendor advisories

github.com/rapid7/insightconnect-plugins/blob/master/plugins/markdown/help.md

Affected products

Product	Affected versions	Fixed in
Rapid7 InsightConnect Markdown Plugin	v < 4.0.2	4.0.2

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