CVE-2026-58504 — draw.io: Stored XSS on file open via editable=0 sibling cell — patch bypass of CVE-2026-46642

Description (CNA)

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 (CNA)

Vendor / product	Versions
jgraph / drawio	affected < 30.2.5

CWE

CWE-79, CWE-116

References

ADP enrichment

CISA-ADP

No English description supplied.

https://github.com/jgraph/drawio/security/advisories/GHSA-c76x-r78m-phwx