CVE-2026-73047: Siyuan-Note Siyuan

Medium severity, CVSS 6.2. EPSS: 0.2% chance of exploitation in the next 30 days.

siyuan versions <= 3.7.3 (fixed in v3.7.4) contain a server-side template injection vulnerability in the attribute-view Template calculation feature (introduced in v3.7.0-beta.1). The feature's template engine uses Sprig's unmodified function map, which still exposes the env, expandenv, and getHostByName functions that were removed elsewhere for CVE-2024-55660. A local, unauthenticated attacker (the kernel binds to 127.0.0.1 by default with no per-UID access control) can inject a malicious Template calculation formula to read environment variables belonging to the account running siyuan — including from a separate, unprivileged OS account — and to perform DNS lookups from the server's network position.

Affected products

• Siyuan-Note Siyuan: before 3.7.4 (fixed in 3.7.4)

Published 2026-08-15. Last modified 2026-08-26.