CVE-2026-123309 · Package
NO FIX YET · SEE WHAT TO DO
In JetBrains IntelliJ IDEA before 2026.3 and 2026.2.4, a Markdown preview served by the built-in web server could store malicious script. A script running in the browser of a developer who views that preview could act with that developer's access.
first public Nov 6, 2026 · 1 source
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Developers running IntelliJ IDEA versions before 2026.3 or 2026.2.4 who use the built-in web server with Markdown preview. The sources do not describe any server-side exposure beyond the IDE itself, so teams that only use updated IDE builds can skip it.
Not affected if updated-ide-version
Who cares intellij-idea, jetbrains, markdown, xss
2026.3 and 2026.2.42026.3 or 2026.2.4, per the sources' affected rangeIn JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 stored XSS was possible on the built-in web server via Markdown preview
This page as .md · .json · CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:L/I:L/A:N
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.
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