CVE-2026-54158: SiYuan: Stored XSS to RCE via attribute-view cell rendering in genAVValueHTML()

Should you act?

Critical, preconditions apply

Severe if exploited, but exploitation needs conditions that may not apply to you. This signal is computed from CISA KEV, EPSS and CVSS data; it is not an editorial verdict.

• Not in CISA KEV, but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
• EPSS 0.5%, percentile 43: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 43% of all scored CVEs (low). EPSS is a probability, not a verdict.
• Needs an account (low (any account)). Exposure depends on who can log in.
• Only applies if your dependency tree includes github.com/siyuan-note/siyuan/kernel (Go) < 0.0.0-20260628153353-2d5d72223df4, fixed in 0.0.0-20260628153353-2d5d72223df4. Check your lockfile, including transitive dependencies.

What it is

SiYuan is an open-source personal knowledge management system. Prior to 3.7.0, the attribute-view (database) cell renderer genAVValueHTML interpolates cell content raw in four of its branches: text, url, phone, and mAsset. A cell value like or "> breaks out of its surrounding tag and runs arbitrary JavaScript in the renderer when the victim opens the block-attribute panel. On Electron desktop the renderer runs with nodeIntegration:true, so the XSS chains to host RCE via require('childprocess'). AV files live under the workspace and ride normal sync, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that opens a panel containing that row.he kernel doesn't escape on the way in either, so the malicious cell persists byte-for-byte. There's no equivalent of the html.EscapeAttrVal call that protects block IAL attributes at kernel/model/blockial.go:261. This vulnerability is fixed in 3.7.0.

From the GitHub advisory

Summary

The attribute-view (database) cell renderer genAVValueHTML interpolates cell content raw in four of its branches: text, url, phone, and mAsset. A cell value like or "> breaks out of its surrounding tag and runs arbitrary JavaScript in the renderer when the victim opens the block-attribute panel. On Electron desktop the renderer runs with nodeIntegration:true, so the XSS chains to host RCE via require('childprocess'). AV files live under the workspace and ride normal sync, so an attacker with write access to any synced workspace plants the payload once and it fires on every device that opens a panel containing that row.

The kernel doesn't escape on the way in either, so the malicious cell persists byte-for-byte. There's no equivalent of the html.EscapeAttrVal call that protects block IAL attributes at kernel/model/blockial.go:261.

Companion advisory: GHSA-mvjr-vv3c-w4qv. Same workspace-sync to renderer-sink to Electron-RCE pattern in the CSS-snippet renderer, different sink file. Worth auditing for the same pattern in other renderers that pull from synced workspace data.

Details

Weakness type: CWE-79, CWE-1188.

Product: github.com/siyuan-note/siyuan/kernel (Go) · Assigned by: GitHub_M · Published: 2026-06-24

Affected and fixed versions

Severity scores

• Attack vector: network (remotely reachable)
• Attack complexity: low
• Privileges required: low (any account)
• User interaction: none
• Scope: changed (can affect other components)

CVSS measures how bad a flaw is if exploited, not how likely exploitation is. Read it next to the exploitation data below.

Exploitation and urgency

• CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
• CISA SSVC assessment: exploitation poc, automatable no, technical impact total.
• FIRST EPSS (model of 2026-10-21): 0.51% probability of exploitation activity in the next 30 days; percentile 43.

Timeline

• 2026-06-24 — CVE record published by GitHub_M
• 2026-06-25 — CVE record last updated
• 2026-07-10 — GitHub-reviewed advisory GHSA-5xfx-xj4h-5p7r published (critical)

Sources and references

Original sources first. Version and fix details should always be confirmed against the vendor or project advisory.

Vulnerability records

1. GitHub Advisory GHSA-5xfx-xj4h-5p7r github.com
2. CVE.org record CVE-2026-54158 cve.org
3. NVD entry CVE-2026-54158 nvd.nist.gov

Other references from the CVE record and advisory

1. github.com github.com

Critical Go advisories · Today’s Security Digest