# CVE-2026-82651: SiYuan missing authorization in history and repo diff endpoints

Source: https://junglewise.ai/threats/cve-2026-82651-siyuan-missing-authorization-in-history-and-repo-diff-endpoints  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2026-08-30. Updated: 2026-09-25  
License: CC BY 4.0 with a link back

CVE-2026-82651 · Severity: medium · CVSS 4.9 · Published 2026-08-30

SiYuan is a personal knowledge management application with note-taking and publishing capabilities. An authenticated administrator can bypass a security guard designed to block access to sensitive files (including plaintext publish passwords and template files) by accessing historical snapshots through the /history and /repo/diff endpoints, potentially exposing credentials and configuration data that should be protected.

Technologies: [github.com/siyuan-note/siyuan/kernel (Go)](https://junglewise.ai/threats/technologies/github-com-siyuan-note-siyuan-kernel), [SiYuan](https://junglewise.ai/threats/technologies/siyuan). Vendors: [Go](https://junglewise.ai/threats/vendors/go), [SiYuan](https://junglewise.ai/threats/vendors/siyuan).

## Quick answers

**Is CVE-2026-82651 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2026-82651 being exploited in the wild.

**How severe is CVE-2026-82651?** Medium severity, with a CVSS score of 4.9, published 30 August 2026.

**Which products and versions are affected?** github.com/siyuan-note/siyuan/kernel (Go) SEMVER:introduced=0,fixed=0.0.0-20260816034002-035bf9a8c311; SiYuan before 3.8.1.

**Is there a fix for CVE-2026-82651?** Yes. github.com/siyuan-note/siyuan/kernel (Go): upgrade to 0.0.0-20260816034002-035bf9a8c311 or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**How is CVE-2026-82651 attacked?** It is attacked over the network, in a hosted service.

**Am I affected by CVE-2026-82651?** Check whether you run github.com/siyuan-note/siyuan/kernel (Go) or SiYuan at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- github.com/siyuan-note/siyuan/kernel (Go): upgrade to 0.0.0-20260816034002-035bf9a8c311 or later

  ```sh
  go get github.com/siyuan-note/siyuan/kernel@v0.0.0-20260816034002-035bf9a8c311
  ```


## Technical details

The vulnerability is a missing authorization check (CWE-862/CWE-200) in two HTTP endpoints: /history/*path and /repo/diff/*path in kernel/server/serve.go. While these endpoints require admin authentication and were meant to be protected by the IsForbiddenAbsPath guard (introduced in a prior advisory GHSA-c8r8-95hg-mp34), they construct file paths independently without calling this guard. An authenticated admin attacker can retrieve historical or diff-view copies of sensitive files such as data/.siyuan/publishAccess.json (containing plaintext publish-mode passwords) and files under data/templates/ that exist in the repository history or diff-checkout directory. The guard successfully protects live file access endpoints but fails to cover these archive/history endpoints. The vulnerability requires admin-level authentication and network access to the affected SiYuan instance (typically port 6806). Patched in version 3.8.1.

## Affected products

- SiYuan SiYuan before 3.8.1

## Identifiers

- CVE-2026-82651
- GHSA-3cm4-ccvw-6xr6
- GO-2026-6662

## Timeline

- 2026-08-30: disclosed
- 2026-08-30: patched: patched in v3.8.1

## References

- [https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3cm4-ccvw-6xr6](https://github.com/siyuan-note/siyuan/security/advisories/GHSA-3cm4-ccvw-6xr6)
- [https://www.vulncheck.com/advisories/siyuan-before-3.8.1-missing-authorization-via-history-and-repo-diff](https://www.vulncheck.com/advisories/siyuan-before-3.8.1-missing-authorization-via-history-and-repo-diff)

## Related threats

- [SiYuan path traversal in web fetch](https://junglewise.ai/threats/cve-2026-126776-siyuan-3-7-0-before-3-8-10-on-windows-contains-a-path-traversal)
- [SiYuan publish filter information disclosure in local storage](https://junglewise.ai/threats/go-2026-6836-siyuan-the-publish-filter-for-local-storage-returns-the-7f022e62)
- [SiYuan path traversal via GLOBALROOT alias bypass](https://junglewise.ai/threats/cve-2026-118680-siyuan-3-8-7-through-3-8-8-fails-to-normalize-windows-globalroot)
- [SiYuan SQL injection in history search](https://junglewise.ai/threats/cve-2026-116170-siyuan-before-v3-8-7-contains-an-sql-injection-vulnerability)
- [SiYuan cross-site scripting in /check-auth redirect](https://junglewise.ai/threats/cve-2026-116167-siyuan-from-2-9-0-before-3-8-7-contains-a-cross-site-scripting)