SiYuan: Path Traversal via Double URL Encoding in /export/ Endpoint (Incomplete Fix Bypass for CVE-2026-30869)

Exploitation

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

CVSS 4.0

7.1 · CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:N/VA:N/SC:N/SI:N/SA:N · score source

EPSS

• CVE-2026-41894: 0.37% estimated exploitation activity in the next 30 days; percentile 31.47 (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 The fix for CVE-2026-30869 in SiYuan v3.5.10 only added a denylist check (IsSensitivePath) but did not address the root cause — a redundant url.PathUnescape() call in serveExport(). An authenticated attacker can use double URL encoding (%252e%252e) to traverse directories and read arbitrary workspace files including the full SQLite database (siyuan.db), kernel log, and all user documents. Details In kernel/server/serve.go, the serveExport() function (line 314-320) processes file paths as follows: Go's HTTP server already decodes percent-encoded characters once during request parsing. The additional url.PathUnescape() call creates a double-decode vulnerability: 1. Attacker sends: GET /export/%252e%252e/siyuan.db 2. Go HTTP decodes %25 → %, result: URL.Path = /export/%2e%2e/siyuan.db 3. Go's path cleaner sees %2e%2e as literal characters (not ..), no redirect occurs 4. url.PathUnescape("%2e%2e") decodes to .. 5. filepath.Join(exportBaseDir, "../siyuan.db") resolves to…

Published by the source

22 Apr 2026, 20:51 UTC

Last modified by the source

27 Apr 2026, 16:34 UTC

Source last checked

26 Oct 2026, 15:19 UTC

1. Revision 1 · created · 26 Oct 2026

   Published from ghsa record GHSA-hjh7-r5w8-5872

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# Patch Next advisory brief: CVE-2026-41894

Advisory: SiYuan: Path Traversal via Double URL Encoding in `/export/` Endpoint (Incomplete Fix Bypass for CVE-2026-30869)
IDs: CVE-2026-41894, GHSA-hjh7-r5w8-5872
Record: https://patchnext.com/advisories/cve-2026-41894 (revision 1, source checked 26 Oct 2026, 15:19 UTC)
Inventory: none attached. This brief comes from a public page and does not say whether any deployment is affected.
Severity: High (CVSS 7.1)
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 3.6.5. A vendor fix does not mean a deployment is fixed.

## Affected components
- Go github.com/siyuan-note/siyuan/kernel: affected < 3.6.5; fixed in 3.6.5

## 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-hjh7-r5w8-5872 (GitHub-reviewed advisory GHSA-hjh7-r5w8-5872 lists affected ranges: Go github.com/siyuan-note/siyuan/kernel >=0 <3.6.5)

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