Which versions of SiYuan are affected by EUVD-2026-25626?

CVE-2026-41894 is a directory traversal vulnerability in SiYuan personal knowledge management system that permits authenticated users to bypass access controls and read arbitrary workspace files,…. A patch is available.

How to fix or mitigate EUVD-2026-25626?

Within 24 hours: Identify all SiYuan deployments and current version numbers in your environment; restrict network access to SiYuan instances to authorized users only and review recent access logs for suspicious file requests. Within 7 days: Contact SiYuan vendor for patch timeline and interim mitigation guidance; implement application-level request logging to detect directory traversal attempts using patterns like %252e%252e. Within 30 days: Apply vendor-released patch immediately upon availability; conduct forensic review of access logs dating back 90 days to identify any potential unauthorized file access.

SiYuan EUVD-2026-25626

Q: What is the CVSS score of EUVD-2026-25626?

EUVD-2026-25626 has a CVSS 4.0 base score of 7.1 (High). CVSS vector: 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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X. EPSS exploitation probability: 0.0%.

| CVE-2026-41894 HIGH

Path Traversal (CWE-22)

2026-04-24 GitHub_M

GHSA-hjh7-r5w8-5872

Path Traversal Siyuan

7.1

CVSS 4.0 · GitHub Advisory

Severity by source

GitHub Advisory PRIMARY

7.1 HIGH

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Primary rating from GitHub Advisory · only source for this CVE.

CVSS VectorGitHub Advisory

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/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X

Attack Vector

Network

Attack Complexity

Low

Privileges Required

Low

User Interaction

None

Scope

Lifecycle Timeline

Patch released

Apr 27, 2026 - 18:53 nvd

Patch available

Re-analysis Queued

Apr 27, 2026 - 14:22 vuln.today

cvss_changed

Patch available

Apr 24, 2026 - 21:02 EUVD

Analysis Generated

Apr 24, 2026 - 19:46 vuln.today

CVSS changed

Apr 24, 2026 - 19:22 NVD

7.1 (HIGH)

EUVD ID Assigned

Apr 24, 2026 - 19:15 euvd

EUVD-2026-25626

Analysis Generated

Apr 24, 2026 - 19:15 vuln.today

CVE Published

Apr 24, 2026 - 18:56 nvd

HIGH 7.1

DescriptionGitHub Advisory

SiYuan is an open-source personal knowledge management system. Prior to 3.6.5, the fix for CVE-2026-30869 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. This vulnerability is fixed in 3.6.5.

AnalysisAI

Directory traversal in SiYuan personal knowledge management system allows authenticated attackers to read arbitrary workspace files via double URL encoding bypass. The vulnerability stems from an incomplete fix for CVE-2026-30869 that added only denylist validation without removing a redundant url.PathUnescape() call in serveExport(). Attackers can use %252e%252e encoding to access sensitive files including the complete SQLite database (siyuan.db), kernel logs, and all user documents. EPSS data not available for this recent CVE; publicly available exploit code exists (GitHub commit demonstrates exploitation technique).

Technical ContextAI

The vulnerability affects SiYuan (CPE: cpe:2.3:a:siyuan-note:siyuan), an open-source personal knowledge management system built in Go. This is a CWE-22 (Improper Limitation of a Pathname to a Restricted Directory) path traversal issue caused by redundant URL decoding. The serveExport() function calls url.PathUnescape() on already-decoded input, creating a double-decode condition. When a client sends %252e (which is % followed by 25 and 2e), the first decode (by HTTP server/router) converts it to %2e, then the redundant PathUnescape() converts %2e to a literal dot. This allows sequences like %252e%252e%252f to bypass the IsSensitivePath denylist check (which occurs before the second decode) and resolve to ../ enabling directory traversal. The previous CVE-2026-30869 fix attempted to block traversal with path validation but failed to address the root cause double-decoding issue.

RemediationAI

Upgrade to SiYuan version 3.6.5 or later immediately, available at https://github.com/siyuan-note/siyuan/releases/tag/v3.6.5. The fix (commit bb481e1290c4a34255652ede85a546504505d2a7) removes the redundant url.PathUnescape() call from serveExport(), eliminating the double-decode condition. If immediate patching is not feasible, implement network-level access controls to restrict SiYuan instances to trusted users only and monitor export endpoint access logs for unusual encoded character sequences (%25). Disable the export functionality entirely if not business-critical by blocking HTTP routes to /export/* endpoints via reverse proxy rules, though this eliminates legitimate export features. Review authentication logs for suspicious account activity and rotate credentials for accounts with access to sensitive workspaces. These workarounds reduce but do not eliminate risk; patching remains the definitive solution.