CVE-2026-82651 SiYuan before v3.8.1 Missing Authorization via /history and /repo/diff
An authenticated administrator can bypass path restrictions to read sensitive historical files, including plaintext passwords, in SiYuan.
- Exploited in the wild
- Not known
- Login needed
- An administrator
- Attackable
- Over the internet
- Victim action needed
- Not needed
- Fix
- Available
What is CVE-2026-82651?
CVE-2026-82651 is a medium-severity missing authorization vulnerability in siyuan-note siyuan, published on 30 Aug 2026. An attacker needs administrator access to exploit it, with no action from the victim.
Official description
SiYuan before v3.8.1 does not apply the IsForbiddenAbsPath guard (introduced in GHSA-c8r8-95hg-mp34) to the /history/*path and /repo/diff/*path endpoints in kernel/server/serve.go. These routes require admin authentication but construct file paths independently, so an authenticated administrator can retrieve historical snapshots of sensitive files that the guard is meant to block, including data/.siyuan/publishAccess.json (plaintext publish-mode passwords) and files under data/templates/.
Weakness: CWE-200
Which versions are affected by CVE-2026-82651?
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 | 0.0.0-20260816034002-035bf9a8c311 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260816034002-035bf9a8c311 |
github.com/siyuan-note/siyuan/kernel Go | All versions | 0.0.0-20260816034002-035bf9a8c311 |
How do I fix CVE-2026-82651?
Upgrade github.com/siyuan-note/siyuan/kernel to 0.0.0-20260816034002-035bf9a8c311 or later.
Upgrade, and check permissions on every request on the server, not only in the interface. More about Missing authorization.
Is CVE-2026-82651 being exploited?
There is no known exploitation of CVE-2026-82651 in the wild and no public exploit code.
Sources
Also known as GHSA-3cm4-ccvw-6xr6, GHSA-j8f5-rf5j-w7pm, GO-2026-6662.