SiYuan: Broken access control in /api/tag/getTag — Reader role can mutate Conf.Tag.Sort and persist to disk

Exploitation

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

CVSS

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

EPSS

• CVE-2026-45147: 0.15% estimated exploitation activity in the next 30 days; percentile 4.37 (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.

Summary POST /api/tag/getTag is registered with model.CheckAuth only, omitting both model.CheckAdminRole and model.CheckReadonly, despite the handler performing a configuration write that is normally guarded by both. Any authenticated user — including publish-service RoleReader accounts and RoleEditor accounts on a read-only workspace — can call this endpoint with a sort argument to mutate model.Conf.Tag.Sort and trigger model.Conf.Save(), which atomically rewrites the entire workspace conf.json. Same root-cause class as the patched GHSA-4j3x-hhg2-fm2x (which fixed missing CheckAdminRole + CheckReadonly on /api/template/renderSprig). Details Affected files / lines (v3.6.5): kernel/api/router.go:170 — only CheckAuth: kernel/api/tag.go:28-64 — handler. The if nil != arg["sort"] block writes config without any role check: Conf.Save() rewrites the entire configuration file, which means a malicious caller racing with a legitimate config change can roll back another user's setting (TOCTOU…

Published by the source

13 May 2026, 15:32 UTC

Last modified by the source

15 May 2026, 23:45 UTC

Source last checked

26 Oct 2026, 15:22 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-6r88-8v7q-q4p2

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# Patch Next advisory brief: CVE-2026-45147

Advisory: SiYuan: Broken access control in `/api/tag/getTag` — Reader role can mutate `Conf.Tag.Sort` and persist to disk
IDs: CVE-2026-45147, GHSA-6r88-8v7q-q4p2
Record: https://patchnext.com/advisories/cve-2026-45147 (revision 1, source checked 26 Oct 2026, 15:22 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: Medium (CVSS 4.3)
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 0.0.0-20260512140701-d7b77d945e0d. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 0.0.0-20260512140701-d7b77d945e0d; fixed in 0.0.0-20260512140701-d7b77d945e0d

## 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://github.com/advisories/GHSA-6r88-8v7q-q4p2 (GitHub-reviewed advisory GHSA-6r88-8v7q-q4p2 lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <0.0.0-20260512140701-d7b77d945e0d)

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