SiYuan before v3.8.4 does not HTML-escape stored flashcard block content before interpolating it into the card-manager list markup. Block content returned by /api/riff/getRiffCards is inserted into a card item template in app/src/card/viewCards.ts and assigned to listElement.innerHTML, so content such as becomes an executable event-handler attribute. Because the SiYuan desktop (Electron) main window is created with nodeIntegration enabled and contextIsolation disabled, an administrator who opens the card manager on a workspace containing attacker-supplied flashcard content (for example introduced through contribution or import) executes the attacker's script in a privileged renderer, which can lead to arbitrary code execution on the host. The affected endpoint remains behind authentication and administrator-role checks; this is an untrusted-content-to-privileged-renderer issue, not an authorization bypass.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-79"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/100xxx/CVE-2026-100641.json"
}{
"extracted_events": [
{
"range": [
{
"introduced": "0"
},
{
"fixed": "3.8.4"
}
],
"source": "AFFECTED_FIELD",
"strategy": "StandardRange"
},
{
"range": [
{
"fixed": "1ecb1c07de497ff03b585536fe5579291754d96b"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "48c354e7de130aaada9d7120125bbc768344fd3b"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "41b14025b4ac4a8379d1200580344ca18ad152b7"
}
],
"source": "REFERENCES_COMMIT"
},
{
"range": [
{
"fixed": "8641553a1f07374001902d3ce773285db1292b2d"
}
],
"source": "REFERENCES_COMMIT"
}
]
}