SiYuan: 17 block metadata/content endpoints in kernel/api/block.go have zero publish-access filtering, reachable by anonymous publish-mode readers

Exploitation

No confirmed exploitation recorded. Patch Next marks exploitation only from CISA KEV.

CVSS

7.5 · CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N

EPSS

• CVE-2026-74904: 0.45% estimated exploitation activity in the next 30 days; percentile 39.08 (FIRST EPSS, 2026-11-03). This is a model estimate, not proof of exploitation or customer exposure.

As published by the source; long descriptions are shortened.

Same CWE-862 family, found via an automated bulk sweep of every /api/block/ handler in kernel/api/block.go for the presence of any access-check reference (IsReadOnlyRoleContext, checkBlockPublishAccess, GetPublishAccess) anywhere in the function body. 17 of 28 candidate endpoints have none. Cross-checked against the file's own sibling functions (getBlockInfo, getBlockDOM, getRefIDs, etc.), which correctly implement the check, confirming this is a real, uneven gap rather than a deliberate design choice for the whole file. Summary 17 handlers in kernel/api/block.go, all gated only by model.CheckAuth with no admin-role requirement, return block content-derived text, structural metadata, or existence information for any block ID supplied, with no access check anywhere in the handler or, for the ones checked in detail, the model functions they call. This is CWE-862 (Missing Authorization), the same class as the companion advisories from this review round, found in a different file via a…

Published by the source

2 Oct 2026, 23:05 UTC

Last modified by the source

7 Oct 2026, 17:45 UTC

Source last checked

26 Oct 2026, 15:29 UTC

1. Revision 3 · amended · 26 Oct 2026

   Amended from ghsa record GHSA-4vpg-gwqq-w44c

2. Revision 2 · amended · 24 Oct 2026

   Amended from osv record GO-2026-6654

3. Revision 1 · created · 24 Oct 2026

   Published from osv record GHSA-4vpg-gwqq-w44c

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# Patch Next advisory brief: CVE-2026-74904

Advisory: SiYuan: 17 block metadata/content endpoints in kernel/api/block.go have zero publish-access filtering, reachable by anonymous publish-mode readers
IDs: CVE-2026-74904, GHSA-4vpg-gwqq-w44c
Record: https://patchnext.com/advisories/cve-2026-74904 (revision 3, source checked 26 Oct 2026, 15:29 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.5)
Exploitation: no confirmed exploitation recorded. Patch Next confirms exploitation only from CISA KEV.
Vendor response: Vendor fix available; fixed versions by package: github.com/siyuan-note/siyuan/kernel 0.0.0-20260804015139-bd067a4fe9b2. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 0.0.0-20260804015139-bd067a4fe9b2; fixed in 0.0.0-20260804015139-bd067a4fe9b2

## Suggested inspection (read-only)
- Go github.com/siyuan-note/siyuan/kernel: check the installed version with your package manager.

## Supported action
Upgrade each affected component to a fixed version on its release line. For a transitive dependency, upgrade the parent package or add an override or constraint, then regenerate the lockfile. Redeploy every environment that ran an affected version.

## Required regression checks
- Run the test suite and a production build.
- Exercise the features that depend on github.com/siyuan-note/siyuan/kernel.
- Repeat the inspection and confirm that only fixed versions remain installed.

## Rollback considerations
- Keep the previous lockfile and deployment artifact. Rolling back reinstates the vulnerable version, so apply any documented mitigation while you fix forward.

## Unresolved questions
- Which deployments run an affected version?
- Exploitation status can change. Check again before lowering the priority.
- Mark the work resolved only after the fixed version is verified in production.

## Sources
- Verified: https://osv.dev/vulnerability/GO-2026-6654 (OSV record GO-2026-6654 lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260804015139-bd067a4fe9b2 (fixed))
- Verified: https://osv.dev/vulnerability/GHSA-4vpg-gwqq-w44c (OSV record GHSA-4vpg-gwqq-w44c lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260804015139-bd067a4fe9b2 (fixed))
- Verified: https://github.com/advisories/GHSA-4vpg-gwqq-w44c (GitHub-reviewed advisory GHSA-4vpg-gwqq-w44c lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260804015139-bd067a4fe9b2)

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