---
title: "CVE-2026-32940: SiYuan has a SanitizeSVG bypass via data:text/xml in getDynamicIcon (incomplete fix for CVE-2026-29183)"
url: https://erroneo.us/security/cve/CVE-2026-32940/
description: "CVE-2026-32940 (github.com/siyuan-note/siyuan (Go)): SiYuan is a personal knowledge management system. In versions 3.6.0 and below, SanitizeSVG has an…"
type: vulnerability-record
section: "Security Digest"
date_published: 2026-03-20
date_modified: 2026-03-20
publisher: erroneo.us
author: erroneo.us Security Desk
cve: "CVE-2026-32940"
kev: false
cvss: 9.3
epss: 0.00476
license: All rights reserved. Quote with attribution and a link.
---

# CVE-2026-32940: SiYuan has a SanitizeSVG bypass via data:text/xml in getDynamicIcon (incomplete fix for CVE-2026-29183)

**Signal:** Critical and remotely reachable. No known exploitation yet, but it is network-reachable without credentials. (Computed from CISA KEV, EPSS and CVSS; not an editorial verdict.)

## Should you act?

- Not in CISA KEV , but CISA’s SSVC assessment records a public proof-of-concept, so attack code exists.
- EPSS 0.5% , percentile 40: FIRST’s model estimates a 0.5% chance of exploitation activity in the next 30 days, higher than 40% of all scored CVEs (low). EPSS is a probability, not a verdict.
- Needs a user to click or open something. Phishing makes that realistic, but it is not wormable.
- Only applies if your dependency tree includes github.com/siyuan-note/siyuan (Go) <= 0.0.0-20260313024916-fd6526133bb3, no fixed version listed . Check your lockfile, including transitive dependencies.

## What it is

SiYuan is a personal knowledge management system. In versions 3.6.0 and below, SanitizeSVG has an incomplete blocklist — it blocks data:text/html and data:image/svg+xml in href attributes but misses data:text/xml and data:application/xml, both of which can render SVG with JavaScript execution. The unauthenticated /api/icon/getDynamicIcon endpoint serves user-controlled input (via the content parameter) directly into SVG markup using fmt.Sprintf with no escaping, served as Content-Type: image/svg+xml. This creates a click-through XSS: a victim navigates to a crafted URL, sees an SVG with an injected link, and clicking it triggers JavaScript via the bypassed MIME types. The attack requires direct navigation to the endpoint or / embedding, since tag rendering in the frontend doesn't allow interactive links. This issue has been fixed in version 3.6.1.

## Affected packages

- Go `github.com/siyuan-note/siyuan` <= 0.0.0-20260313024916-fd6526133bb3 → fixed: none listed

## Affected products (CVE record)

- siyuan-note siyuan: < 3.6.1

## Severity

- GitHub_M CVSS 3.1: 9.3 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N`
- GitHub CVSS 3.1: 9.3 `CVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:C/C:H/I:H/A:N`

## Exploitation

- CISA KEV: not listed (no confirmed in-the-wild exploitation known to CISA).
- CISA SSVC assessment: exploitation poc , automatable no , technical impact partial .
- FIRST EPSS (model of 2026-10-21): 0.48% probability of exploitation activity in the next 30 days; percentile 40.

## Sources

- [GitHub Advisory GHSA-4mx9-3c2h-hwhg](https://github.com/advisories/GHSA-4mx9-3c2h-hwhg)
- [CVE.org record CVE-2026-32940](https://www.cve.org/CVERecord?id=CVE-2026-32940)
- [NVD entry CVE-2026-32940](https://nvd.nist.gov/vuln/detail/CVE-2026-32940)
- [github.com](https://github.com/siyuan-note/siyuan/security/advisories/GHSA-4mx9-3c2h-hwhg)
- [github.com](https://github.com/siyuan-note/siyuan/commit/d01d561875d4f744e9f6232f1d4831e3642b8696)
- [github.com](https://github.com/advisories/GHSA-6865-qjcf-286f)
- [github.com](https://github.com/siyuan-note/siyuan/releases/tag/v3.6.1)

---
Source page: https://erroneo.us/security/cve/CVE-2026-32940/ · Security Digest: https://erroneo.us/security/ · More: https://erroneo.us/llms.txt