CVE-2026-84803 — SiYuan before v3.8.2 Stored XSS via incomplete asset blocklist
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in asset serving due to an incomplete extension blocklist that misses script-capable file types. Attack…
Published: 2026-09-02 · CVSS: 8.6 · CVSS 4.0
SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in asset serving due to an incomplete extension blocklist that misses script-capable file types. Attackers can upload files with extensions like .xht, .ehtml, .xsl, .xbl, or .rdf that resolve to executable media types and execute JavaScript to steal API tokens and compromise workspaces.
Source: CVE Program · Revision 8b16575c39f1e1810c5e863010da073d2d3285e7