Siyuan before v3.8.2 contains an information disclosure vulnerability in the POST /api/search/fullTextSearchBlock endpoint that filters private blocks from results but returns unfiltered match counts. Unauthenticated publish-mode readers can submit arbitrary search terms to learn whether matching content exists in hidden or unpublished documents and determine the number of matching blocks and pages.
{
"cna_assigner": "VulnCheck",
"cwe_ids": [
"CWE-200"
],
"osv_generated_from": "https://github.com/CVEProject/cvelistV5/tree/main/cves/2026/87xxx/CVE-2026-87810.json"
}{
"extracted_events": [
{
"introduced": "0"
},
{
"fixed": "3.8.2"
},
{
"fixed": "v3.8.2"
}
],
"source": [
"AFFECTED_FIELD",
"DESCRIPTION"
]
}