Critical SiYuan Stored XSS Flaw Enables RCE in Electron Desktop Client
SiYuan disclosed a critical stored cross-site scripting vulnerability that can escalate to remote code execution in its Electron desktop client. The flaw affects versions prior to 3.7.0 and stems from unsafe HTML rendering in attribute-view cells, including the genAVValueHTML() function and asset cell handling, where attacker-controlled content in text, URL, phone, and asset fields is inserted into innerHTML without proper escaping. Researchers said the issue can be triggered when a victim opens a note, loads the block-attribute panel for a crafted row, or in some cases hovers over malicious content that is re-rendered through tooltip HTML.
The impact is amplified by insecure Electron settings, notably nodeIntegration: true and contextIsolation: false, which allow injected JavaScript to reach Node.js APIs and execute system commands. Malicious payloads can be stored unchanged in workspace attribute-view JSON data, then spread through normal sync or collaborative workflows and execute on other devices that render the affected content. The vulnerability is tracked as CVE-2026-54158, carries a CVSS 9.9 rating, and has been fixed in SiYuan 3.7.0; advisories recommend upgrading and applying stronger output encoding and safer Electron hardening to prevent similar XSS-to-RCE chains.
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4 events from the most recent confirmed update back to the earliest known activity.
CVE-2026-54158 published with critical severity
CVE-2026-54158 was published on June 24, 2026 as a critical SiYuan vulnerability with a CVSS 3.1 score of 9.9. The entry describes a stored XSS flaw in genAVValueHTML() that can escalate to remote code execution on Electron desktop deployments.
SiYuan 3.7.0 fixes CVE-2026-54158
The CVE entry states the stored XSS-to-RCE issue tracked as CVE-2026-54158 is fixed in SiYuan version 3.7.0. Affected versions are those prior to 3.7.0.
GitHub advisories disclose stored XSS-to-RCE flaws in SiYuan
Two GitHub security advisories published on June 3, 2026 disclosed stored XSS vulnerabilities in SiYuan's attribute-view rendering, including unsafe asset cell and genAVValueHTML() handling. Both reports state the flaws can lead to remote code execution in the Electron desktop client because of insecure renderer settings.
SiYuan v3.6.5 released with vulnerable attribute-view rendering
The advisory identifies affected code at commit HEAD 96dfe0b, corresponding to SiYuan v3.6.5 dated 2026-04-21. This version contains stored XSS flaws in attribute-view cell rendering that can be escalated to RCE in Electron desktop builds.
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CVE-2026-54158 - SiYuan: Stored XSS to RCE via attribute-view cell rendering in genAVValueHTML()
cvefeed.io
Open sourceStored XSS to RCE via Unsanitized Attribute View Asset Cell Content · Advisory · siyuan-note/siyuan · GitHub
github.com
Open sourceStored XSS to RCE via attribute-view cell rendering in genAVValueHTML() · Advisory · siyuan-note/siyuan · GitHub
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SiYuan Flaws Exposed Files and Enabled Desktop Command Execution
SiYuan disclosed two high-severity vulnerabilities affecting its personal knowledge management platform, including an arbitrary file-read issue tracked as **`CVE-2026-32938`** and a stored XSS flaw tracked as **`CVE-2026-34448`**. In SiYuan **3.6.0 and earlier**, the desktop publish service endpoint **`/api/lute/html2BlockDOM`** could copy local files referenced through **`file://`** links into the workspace assets directory without properly validating sensitive paths. Because authenticated users could then access **`GET /assets/*path`**, a publish-service visitor could exfiltrate readable local files from the desktop environment. The issue was fixed in **3.6.1**. A separate flaw in SiYuan **before 3.6.2** allowed an attacker to plant a malicious URL in an Attribute View field and trigger stored XSS when a victim opened Gallery or Kanban views configured with **"Cover From -> Asset Field"**. The application accepted arbitrary HTTP(S) URLs without extensions as images and injected them into an **`<img src="...">`** attribute without escaping. In the Electron desktop client, where **`nodeIntegration`** was enabled and **`contextIsolation`** was disabled, the XSS could escalate to arbitrary operating-system command execution under the victim’s account. SiYuan patched the command-execution path in **3.6.2**, leaving affected organizations to prioritize upgrades across both releases.
Apr 1, 2026
SiYuan Mermaid Rendering Flaws Expose NTLM Hashes and Enable Electron RCE
GitHub security advisories disclosed two high-severity vulnerabilities in **SiYuan** that stem from unsafe Mermaid diagram rendering in versions `3.6.3` and earlier. In `CVE-2026-40107`, SiYuan rendered Mermaid content with `securityLevel="loose"` and `htmlLabels` enabled, allowing attacker-controlled `img` tags to survive sanitization and be injected into SVG `foreignObject` content through `innerHTML`. When a victim opens a malicious note, the Electron client can fetch an attacker-controlled URL; on Windows, protocol-relative paths may resolve to UNC shares and trigger automatic SMB authentication, leaking the victim's **NTLMv2** hash. The issue was fixed in version `3.6.4` and mapped to `CWE-918`. A second flaw, `CVE-2026-40322`, used the same Mermaid configuration weakness to allow `javascript:` links to persist in rendered SVG output, creating a stored **XSS** condition. In SiYuan's Electron desktop application, where `nodeIntegration` was enabled and `contextIsolation` disabled, the bug could be escalated to arbitrary code execution if a user opened a malicious note and clicked the rendered diagram node. The vulnerability affects the same pre-`3.6.4` release line and is mapped to `CWE-79` and `CWE-94`, with advisory details describing high impact to confidentiality, integrity, and availability.
Apr 17, 2026
Critical RCE in SiYuan Bazaar Lets Malicious Packages Run OS Commands
SiYuan disclosed **CVE-2026-56395**, a critical remote code execution flaw affecting versions before `3.6.1`. The bug stems from improper sanitization of Bazaar marketplace package metadata and `README` content, allowing malicious package authors to inject arbitrary HTML and JavaScript into fields including `displayName`, `description`, and `README`. When a user browses the Bazaar, the injected payload can trigger cross-site scripting and, because the Electron application has `nodeIntegration` enabled, escalate to execution of operating system commands on the victim device. The vulnerability has been rated critical, with reported scores of **9.6 CVSS v3.1** and **9.4 CVSS v4.0**; remediation is to upgrade to **SiYuan 3.6.1 or later** and avoid installing packages from untrusted sources.
Jun 21, 2026