CVE-2026-40262
8.7 · HIGHOverview
CVE-2026-40262 is a high-severity vulnerability. It was published on April 17, 2026 and has a CVSS 3.1 base score of 8.7 (HIGH).
This vulnerability has a CVSS 3.1 base score of 8.7, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical Description
Note Mark is an open-source note-taking application. In versions 0.19.1 and prior, the asset delivery handler serves uploaded files inline and relies on magic-byte detection for content type, which does not identify text-based formats such as HTML, SVG, or XHTML. These files are served with an empty Content-Type, no X-Content-Type-Options: nosniff header, and inline disposition, allowing browsers to sniff and render active content. An authenticated user can upload an HTML or SVG file containing JavaScript as a note asset, and when a victim navigates to the asset URL, the script executes under the application's origin with access to the victim's authenticated session and API actions. This issue has been fixed in version 0.19.2.
Remediation
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Frequently Asked Questions
What is CVE-2026-40262?
CVE-2026-40262 is a high-severity vulnerability. It was published on April 17, 2026 and has a CVSS 3.1 base score of 8.7 (HIGH).
How severe is CVE-2026-40262?
This vulnerability has a CVSS 3.1 base score of 8.7, rated HIGH. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-40262?
Check the references section for vendor advisories, patches, and mitigation guidance. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-40262?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-40262 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
AI agents map your attack surface to find vulnerabilities like this one.
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