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Full vulnerability report · 2026
CVE-2026-75917High confidence

SiYuan before v3.7.4 XSS-to-RCE via pathName.ts

siyuan-note · siyuan

Official source article: GitHub GHSA-JJQ3-3942-X99R ↗. Check the applicable product and release in the original source.

9.3CriticalCVSS 4.0
Recommended action
Within 72 hours

Critical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.

Patch available
R
Operational reassessment

Published severity in operational context

Open reassessment dashboard →
Published severityCriticalOperational priority:Critical, unchanged from published severity.unchanged

Evidence used

  • No CISA KEV confirmation is currently recorded.
  • A structured source references public exploit or proof-of-concept material.
  • EPSS is 0.24% for the current model date.

Compensating controls

  • Validate the affected product branch and deploy the verified fixed release.
  • Restrict local access and enforce least privilege on affected hosts.
  • Increase monitoring for the attack path and post-exploitation behaviour described in the report.

Verification

  1. Confirm that the asset runs siyuan-note siyuan and falls inside the recorded affected range.
  2. Verify the installed build against the product-specific fixed version after deployment.
  3. Validate exposure, authentication requirements and compensating controls in the actual environment.
  4. Reopen this reassessment when CVSS, KEV, EPSS, exploit evidence or remediation changes.
Mitigation target: Within 3 daysRemediation target: Within 90 days

This automated reassessment organises public evidence. It does not know asset exposure, business impact or control effectiveness and does not replace CVSS or a human risk decision.

Optional official sources

National CERT insights
?CERT means Computer Emergency Response Team; CSIRT is the closely related term Computer Security Incident Response Team.

Choose official national sources for this report. Each advisory shows its original language. Your selection is remembered on this device and included in shared links.

Official European source

ENISA European Vulnerability Database

Official EUVD identifiers, advisory evidence and known-exploited context. Missing fields are not treated as evidence of low risk.

1 current
ENISA EUVD identifier

EUVD-2026-62442

No EUVD known-exploited evidence

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.

EUVD state
Present in the current official mapping
Known exploitation
Not present in the current ENISA EUVD known-exploited dataset. This is not proof of no exploitation.
ENISA score
9.3 · CVSS 4.0
Advisory evidence
No linked advisory details stored yet
Recommended actionWithin 72 hours

Critical technical impact and a public exploit reference; no CISA KEV confirmation is currently recorded.

Patch available
01

What, why and how

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.

What

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.

Why

Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.

How

An attacker operating through local access may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

What

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.

Why

Attacker-controlled content can reach a browser as executable script without sufficient output encoding or sanitisation.

How

An attacker operating through local access may attempt exploitation when the stated preconditions are met. If successful, the issue may cause the confidentiality, integrity or availability impact described by the vendor.

02

Exploit reality and attack path

CVSS severity, EPSS forecast probability, public exploit material and CISA-confirmed exploitation are separate signals.

Observed exploitation
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
No confirmed evidence

No CISA KEV match was present at the last successful refresh. This means no confirmation from that source, not proof of no exploitation.

Public PoC / exploit material
?Confirmed exploitation and public exploit material are separate signals. Attacks can occur without public proof-of-concept or exploit code.
Reference recorded

CISA Vulnrichment records proof-of-concept exploitation in its SSVC data. BlackTree has not independently executed or validated exploit material.

Likely attack path
local access → Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') → cause the confidentiality, integrity or availability impact described by the vendor
Attack surface
Local
Privileges required
None: unauthenticated exploitation is possible
User interaction
Passive interaction required
Attack complexity
Low: no specialised conditions are recorded
Security boundary
Not a CVSS 4.0 base metric
Weakness
?CWE means Common Weakness Enumeration: a standard category for the underlying weakness.
CWE-79 ↗

CWE-79: Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting'). The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.

CVSS vector
?CVSS means Common Vulnerability Scoring System. The vector records the metric values used to calculate technical severity.
CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:P/VC:H/VI:H/VA:H/SC:H/SI:H/SA:H

Common Vulnerability Scoring System 4.0: the compact vector below is decoded into plain language.

AVLocalAttack vector: The attacker needs local access to the vulnerable system.ACLowAttack complexity: No specialised conditions are required beyond attacker-controlled input.ATNoneAttack requirements: No additional deployment or execution condition is required.PRNonePrivileges required: The attacker does not need an account or existing privileges.UIPassiveUser interaction: A user must unknowingly interact with the vulnerable system.VCHighVulnerable-system confidentiality: A successful attack can cause a major loss.VIHighVulnerable-system integrity: A successful attack can cause a major loss.VAHighVulnerable-system availability: A successful attack can cause a major loss.SCHighSubsequent-system confidentiality: A successful attack can cause a major loss.SIHighSubsequent-system integrity: A successful attack can cause a major loss.SAHighSubsequent-system availability: A successful attack can cause a major loss.
Post-exploitation / living off the land
The issue can support a local privilege or sandbox boundary transition; normal system utilities may then be available in the gained context.
UnauthenticatedCWE-79Public exploit reference
A

Official authority intelligence

Only matched European and national findings are included. Language selectors and unavailable sources are omitted.

ENISA EUVD · EUVD-2026-62442Official EUVD mapping

SiYuan before v3.7.4 contains a cross-site scripting vulnerability in the file-tree picker's hover-tooltip generation (app/src/util/pathName.ts, getLeaf()/movePathTo()) used by the 'move/link to' path-selection dialogs, where document metadata fields (bookmark, alias, memo, and an alternate name field) are concatenated into the aria-label HTML attribute without escaping. A document crafted with a double quote in any of these fields breaks out of the attribute context and injects arbitrary HTML attributes including inline event handlers (e.g., onmouseover). Because every SiYuan Electron BrowserWindow runs with nodeIntegration:true, contextIsolation:false, and no CSP, the injected handler gains require('child_process') access, escalating the XSS to arbitrary OS command execution when a victim merely hovers over the malicious document entry in the path-picker dialog. Malicious documents reach victims via sharing, sync, or import.

Official EUVD record ↗
Cyber Security Agency of Singapore · English · CSA-SB-20260826Security Bulletin 26 Aug 2026

The Cyber Security Agency of Singapore included this CVE in its official Security Bulletin 26 Aug 2026, published on 26 August 2026. Open the linked bulletin for the product, severity and reference information published in that issue.

Official advisory ↗
03

Patch and workaround

Operational remediation based on structured source evidence.

Status
?Patch availability is based on structured fixed-version fields and authoritative update references. If no fix is verified, check the vendor advisory before making a change.
Patch available
Affected
siyuan: < 3.7.4
Fixed
siyuan: 3.7.4
Action
Review the linked authoritative reference and apply the recorded fixed release appropriate to the affected product branch.
Workaround
No verified workaround is recorded. Limit untrusted access and use least privilege until authoritative guidance is available.
04

Evidence and provenance

Published 19 Aug 2026 · Last source change 20 Aug 2026, 17:23 UTC · CWE-79 · Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')

CVE recordCVE.org · 5.2
CVSS sourceCNA
EPSS source
?The date BlackTree first stored a score for this CVE from the daily FIRST EPSS feed.
FIRST · tracked since 2026-08-23
European sourceENISA EUVD · EUVD-2026-62442
Product sourceCNA
Remediation sourceCVE/CNA references
CWE sourceCNA
NVD statusNVD not scheduled

Core structured fields are present and their contributing authorities are shown above.

Material change intelligence

What changed after publication

View recent updates ↗
  1. Public exploit evidencePublic exploit evidence changed from No public exploit to Public exploit reference.
    Before
    No public exploit
    After
    Public exploit reference
    CVE.org ↗
  2. Catalogue recordCVE added to the BlackTree catalogue.
    CNA ↗
Material fields only · duplicate refreshes suppressed · history retained for the configured operational retention period
CVE published
Fixed release or patch reference recorded
ENISA EUVD · EUVD-2026-62442↗CISA Vulnrichment SSVC evidence↗CVE authority or vendor reference · GitHub GHSA-JJQ3-3942-X99R↗Official CVE record (CNA and ADP data)↗NVD record↗
Technical terms and abbreviations used in this report
CVE
Common Vulnerabilities and Exposures: the public identifier for one disclosed vulnerability.
CVSS
Common Vulnerability Scoring System: a technical severity framework; it is not patching priority by itself.
EPSS
Exploit Prediction Scoring System: FIRST's estimate of the probability that exploitation activity will be observed in the next 30 days; it is a forecast, not confirmation.
CWE
Common Weakness Enumeration: the standard category describing the underlying software or hardware weakness.
CNA
CVE Numbering Authority: an organisation authorised to assign and publish CVE records.
CISA ADP
Cybersecurity and Infrastructure Security Agency Authorized Data Publisher: structured enrichment added to a CVE record.
NVD
National Vulnerability Database: NIST's enrichment service for CVE records.
CERT / CSIRT
A computer security incident response team that publishes warnings or coordinates incident response.
PoC
Proof of concept: public material that demonstrates or helps reproduce exploitation.
CSAF
Common Security Advisory Framework: a machine-readable format for security advisories.
LoTL
Living off the land: abuse of legitimate tools or system functions during an attack.
Free version - for non-commercial use only.CVE-2026-75917 · cve.blacktree.nl