CVE-2026-123309Medium· 6.1▾ SunlitIn JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 stored XSS was possible on the built-in web server via Markdown preview
▾ Sunlit zone — Low / medium · no exploitation signal
impact 33.6 · likelihood 0 · exploitation 0
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Stakeholder-Specific Vulnerability Categorization from CISA's ADP record at CVE.org: whether exploitation is observed, whether an attack can be automated, and how much of the system is at stake. The CVSS score shown above comes from the assigning CNA record, not NVD.
In JetBrains IntelliJ IDEA before 2026.3, 2026.2.4 stored XSS was possible on the built-in web server via Markdown preview
intellij_idea < 2026.3, 2026.2.4Refer to the linked advisories for vendor-supplied fixes and affected version ranges.
Connected by shared product, vendor, weakness, or advisory.
CVE-2026-123301High· 8.2In JetBrains IntelliJ IDEA before 2026.3 dOM-based XSS in the OpenAPI preview error view was possible
CVE-2026-123837High· 7.8In JetBrains IntelliJ IDEA before 2026.3, 2026.2.1 command injection was possible in untrusted projects via Tomcat run configurations on WSL
CVE-2026-123838High· 7.8In JetBrains IntelliJ IDEA before 2026.3 code execution was possible in Safe Mode via UI Designer form file
CVE-2026-123840Medium· 4.7In JetBrains IntelliJ IDEA before 2026.3 hTML injection was possible in Remote Development editor tabs
CVE-2026-123841High· 7.8In JetBrains IntelliJ IDEA before 2026.3 code execution was possible via symlinks in an imported settings archive
CVE-2026-123846Medium· 4.3In JetBrains IntelliJ IDEA before 2026.3 blind SSRF was possible via remote references in JSON Schema validation