CVE-2026-8661

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.

CVSS v3 4.8 MEDIUM

4.8^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.2 / Impact : 2.5

Attack Vector NETWORK

Attack Complexity HIGH

Privileges Required NONE

User Interaction NONE

Confidentiality Impact LOW

Integrity Impact LOW

Availability Impact NONE

Scope UNCHANGED

References

Link	Resource
https://github.com/rapid7/insightconnect-plugins/blob/master/plugins/markdown/help.md
https://github.com/rapid7/insightconnect-plugins/pull/3721
https://github.com/rapid7/insightconnect-plugins/pull/4010

Configurations

No configuration.

History

No history.

Information

Published : 2026-06-26 02:16

Updated : 2026-07-24 04:16

NVD link : CVE-2026-8661

Mitre link : CVE-2026-8661

CVE.ORG link : CVE-2026-8661

JSON object : View

Products Affected

No product.

CWE

CWE-79

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CWE-918

Server-Side Request Forgery (SSRF)

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