CVE-2026-123850 · Vendor
NO FIX YET · SEE WHAT TO DO
Before version 2026.2.19422, YouTrack let CSS be injected into Mermaid diagrams through configuration directives. An attacker who can get a crafted diagram rendered could alter how the page looks, with limited impact beyond that.
first public Nov 6, 2026 · 1 source
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Teams that self-host JetBrains YouTrack with Mermaid diagrams enabled in issues or articles. The sources do not say whether hosted YouTrack Cloud instances were patched by the vendor already.
Not affected if mermaid-diagrams-unused, youtrack-cloud
Who cares jetbrains, self-hosted, youtrack
2026.2.19422 are affected.2026.2.19422 or later.In JetBrains YouTrack before 2026.2.19422 cSS injection was possible in Mermaid diagrams via configuration directives
This page as .md · .json · CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:N/I:L/A:N
NVD data is provided by NIST and is public domain. Posts quoted belong to their authors.
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