Medium severity · published Jun 26, 2026
CVE-2026-8661
Server-Side Cross-Site Scripting and SSRF in Rapid7 InsightConnect Markdown to PDF Plugin
4.8
CVSS
0.4%
EPSS
No
On KEV
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.
CVSS vector
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:L/I:L/A:N
Attack vector
Network
Complexity
High
Privileges
None
User interaction
None
Confidentiality
Low
Integrity
Low
Availability
None
Scope
Unchanged
Exploitation
Is it being used?
Exploit prediction (EPSS)0.4% · higher than 31% of CVEs
Exploited in the wildNo evidence yet
CISA KEVNot listed
Ransomware campaign useNot known
Affected products
Which versions
IM
InsightConnect Markdown Plugin · Rapid7
before 4.0.2 · source: vendor
References
NVD
https://nvd.nist.gov/vuln/detail/CVE-2026-8661
CVE.org
https://www.cve.org/CVERecord?id=CVE-2026-8661
github.com
https://github.com/rapid7/insightconnect-plugins/blob/master/plugins/markdown/help.md
github.com
https://github.com/rapid7/insightconnect-plugins/pull/3721
github.com
https://github.com/rapid7/insightconnect-plugins/pull/4010