CVE-2026-8661 (GCVE-0-2026-8661)

Vulnerability from cvelistv5 – Published: 2026-06-26 01:59 – Updated: 2026-07-24 03:10
VLAI
Title
Server-Side Cross-Site Scripting and SSRF in Rapid7 InsightConnect Markdown to PDF Plugin
Summary
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.
Severity
4.8 (Medium)
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-06-26 12:23 UTC
CWE
  • CWE-79 - Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
  • CWE-918 - Server-Side Request Forgery (SSRF)
Assigner
References
Impacted products
Vendor Product Version CPE status
Rapid7 InsightConnect Markdown Plugin Affected: 0 , < 4.0.2 (custom)
Unaffected: 4.0.2 (custom)
guessed Create a notification for this product.
Credits
Jacob Steadman, Rapid7 Jed Starr, Rapid7 SnailSploit (Kai Aizen)
Show details on NVD website
To clipboard 

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