CVE-2026-58504: Jgraph Drawio

Medium severity, CVSS 6.1. EPSS: 0.3% chance of exploitation in the next 30 days.

draw.io is a configurable diagramming and whiteboarding application. Prior to version 30.2.5, opening or importing a crafted .drawio file can execute attacker-controlled JavaScript in the draw.io origin when selected cells are processed by TextFormatPanel.addFont() in src/main/webapp/js/grapheditor/Format.js. An HTML sibling cell keeps the formatted-label path enabled while an editable=0 plain-text sibling is excluded from the merged selection style but remains in the iteration set. graph.cellRenderer.getLabelValue() returns that plain-text label without HTML encoding, and mxUtils.canConvertHtmlToSvg() parses it as HTML, bypassing the earlier CVE-2026-46642 remediation. Successful exploitation can expose diagram data, browser storage, non-HttpOnly cookies, and same-origin actions available to the victim. This issue is fixed in version 30.2.5.

Affected products

• Jgraph Drawio: before 30.2.5 (fixed in 30.2.5)

Published 2026-09-21. Last modified 2026-09-29.