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

Vulnerability from cvelistv5 – Published: 2026-06-26 01:59 – Updated: 2026-06-26 12:24
VLAI
Title
Server-Side Cross-Site Scripting and SSRF in Rapid7 InsightConnect Markdown to PDF Plugin
Summary
Server-Side Cross-Site Scripting and Server-Side Request Forgery vulnerability in the markdown_to_pdf action of Rapid7 InsightConnect Markdown Plugin version 3.1.4 and earlier on Linux allows remote attackers to execute JavaScript server-side and make arbitrary outbound HTTP requests via crafted content embedded in Markdown input. The PDF rendering engine does not restrict script execution or outbound network access.
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 (v2.0.3)
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
Rapid7 InsightConnect Markdown Plugin Affected: 0 , < 4.0.0 (custom)
Unaffected: 4.0.0 (custom)
Create a notification for this product.
Credits
Jacob Steadman, Rapid7 Jed Starr, Rapid7
Show details on NVD website
To clipboard 

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Forecast uses a logistic model when the trend is rising, or an exponential decay model when the trend is falling. Fitted via linearized least squares.

Sightings

Author Source Type Date Other

Nomenclature

  • Seen: The vulnerability was mentioned, discussed, or observed by the user.
  • Confirmed: The vulnerability has been validated from an analyst's perspective.
  • Published Proof of Concept: A public proof of concept is available for this vulnerability.
  • Exploited: The vulnerability was observed as exploited by the user who reported the sighting.
  • Patched: The vulnerability was observed as successfully patched by the user who reported the sighting.
  • Not exploited: The vulnerability was not observed as exploited by the user who reported the sighting.
  • Not confirmed: The user expressed doubt about the validity of the vulnerability.
  • Not patched: The vulnerability was not observed as successfully patched by the user who reported the sighting.


Detection rules are retrieved from Rulezet.