CVE-2026-73047: siyuan before v3.7.4 Server-Side Template Injection via attribute-view
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 Software
Remediation
Recommended actions to resolve this vulnerability, in priority order.
- Upgrade
Upgrade
siyuanto a version that resolves this vulnerability.Fixed in 3.7.4 - Compensating control
If you cannot immediately upgrade, restrict local access to the kernel/service bound to 127.0.0.1 by default (add firewall/host-based ACL rules) to prevent untrusted local processes from reaching the template calculation attribute-view endpoint.
Event History
Frequently Asked Questions
What is the severity of CVE-2026-73047?
CVE-2026-73047 has a medium severity score of 6.2.
How do I fix CVE-2026-73047?
To fix CVE-2026-73047, upgrade SiYuan to version 3.7.4 or later.
What is the risk associated with CVE-2026-73047?
CVE-2026-73047 has a risk rating of 36, indicating a moderate level of concern.
What kind of vulnerability is CVE-2026-73047?
CVE-2026-73047 is a server-side template injection vulnerability.
What software is affected by CVE-2026-73047?
CVE-2026-73047 affects SiYuan versions 3.7.3 and earlier.