CVE-2026-8661: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Rapid7 InsightConnect Markdown Plugin
CVE-2026-8661 is a server-side cross-site scripting (XSS) and server-side request forgery (SSRF) vulnerability in the markdown_to_pdf action of the Rapid7 InsightConnect Markdown Plugin version 3.1.4 and earlier on Linux. This vulnerability allows remote attackers to execute JavaScript code on the server and make arbitrary outbound HTTP requests by embedding crafted content in Markdown input. The PDF rendering engine does not restrict script execution or outbound network access, leading to these security issues.
AI Analysis
Technical Summary
The vulnerability CVE-2026-8661 affects the markdown_to_pdf action in Rapid7 InsightConnect Markdown Plugin versions 3.1.4 and earlier on Linux. It involves improper neutralization of input during web page generation (CWE-79), enabling server-side cross-site scripting and server-side request forgery. Attackers can embed malicious JavaScript in Markdown input, which the PDF rendering engine executes without restriction, allowing arbitrary script execution on the server and outbound network requests. This can lead to information disclosure or interaction with internal/external systems via SSRF.
Potential Impact
Successful exploitation allows remote attackers to execute JavaScript code on the server side and perform arbitrary outbound HTTP requests. This can lead to limited confidentiality and integrity impacts, such as unauthorized data access or manipulation through SSRF. The CVSS score is 4.8 (medium severity), reflecting the need for attacker network access and high attack complexity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround has been documented at this time. Users should monitor Rapid7 advisories for updates and consider restricting or sanitizing Markdown input to reduce risk until a patch is available.
CVE-2026-8661: CWE-79 Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') in Rapid7 InsightConnect Markdown Plugin
Description
CVE-2026-8661 is a server-side cross-site scripting (XSS) and server-side request forgery (SSRF) vulnerability in the markdown_to_pdf action of the Rapid7 InsightConnect Markdown Plugin version 3.1.4 and earlier on Linux. This vulnerability allows remote attackers to execute JavaScript code on the server and make arbitrary outbound HTTP requests by embedding crafted content in Markdown input. The PDF rendering engine does not restrict script execution or outbound network access, leading to these security issues.
CVSS v3.1
Score 4.8medium
Affected software
Weaknesses
AI-Powered Analysis
Machine-generated threat intelligence
Technical Analysis
The vulnerability CVE-2026-8661 affects the markdown_to_pdf action in Rapid7 InsightConnect Markdown Plugin versions 3.1.4 and earlier on Linux. It involves improper neutralization of input during web page generation (CWE-79), enabling server-side cross-site scripting and server-side request forgery. Attackers can embed malicious JavaScript in Markdown input, which the PDF rendering engine executes without restriction, allowing arbitrary script execution on the server and outbound network requests. This can lead to information disclosure or interaction with internal/external systems via SSRF.
Potential Impact
Successful exploitation allows remote attackers to execute JavaScript code on the server side and perform arbitrary outbound HTTP requests. This can lead to limited confidentiality and integrity impacts, such as unauthorized data access or manipulation through SSRF. The CVSS score is 4.8 (medium severity), reflecting the need for attacker network access and high attack complexity.
Mitigation Recommendations
Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. No official fix or temporary workaround has been documented at this time. Users should monitor Rapid7 advisories for updates and consider restricting or sanitizing Markdown input to reduce risk until a patch is available.
Technical Details
- Data Version
- 5.2
- Assigner Short Name
- rapid7
- Date Reserved
- 2026-05-15T06:29:03.740Z
- Cvss Version
- 3.1
- State
- PUBLISHED
- Remediation Level
- null
Threat ID: 6a3de0e34853345fc10869ea
Added to database: 06/26/2026, 02:16:03 UTC
Last enriched: 06/26/2026, 02:30:57 UTC
Last updated: 06/26/2026, 02:30:57 UTC
Views: 3
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