CVE-2026-72812 SiYuan before v3.7.4 Missing Authorization via refreshBacklink
Attackers can trigger persistent server-side writes and resource amplification via an unauthenticated API endpoint, bypassing read-only protections.
- Exploited in the wild
- Not known
- Login needed
- Not needed
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-72812?
CVE-2026-72812 is a medium-severity missing authorization vulnerability in siyuan-note siyuan, published on 14 Aug 2026. An attacker can exploit it over the internet without logging in, with no action from the victim.
Official description
SiYuan versions before v3.7.4 contain a missing authorization vulnerability in the /api/ref/refreshBacklink endpoint that allows anonymous readers to trigger persistent server-side writes. Attackers can invoke the endpoint with an attacker-controlled block ID to flush transaction queues, scan all references globally, and enqueue database writes, bypassing read-only protections and enabling resource amplification attacks.
Weakness: CWE-862
Which versions are affected by CVE-2026-72812?
3 open source packages ship an affected version, including github.com/siyuan-note/siyuan/kernel.
| Package | Affected | Fixed in |
|---|---|---|
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260723002528-7d273c271ce1 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260723002528-7d273c271ce1 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260723002528-7d273c271ce1 |
How do I fix CVE-2026-72812?
Upgrade github.com/siyuan-note/siyuan/kernel to 0.0.0-20260723002528-7d273c271ce1 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-72812 being exploited?
There is no known exploitation of CVE-2026-72812 in the wild and no public exploit code.
Sources
Also known as GHSA-wgwx-479j-23vq, GO-2026-6408.