# CVE-2026-25647: Lute has a Stored Cross-Site Scripting (XSS) via Markdown hyperlink

> Attackers can inject malicious JavaScript via Markdown hyperlinks, executing code in victim sessions when rendered.

- **Severity:** Medium 4.6 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:L/I:L/A:N`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** A user has to click or open something
- **Fix available:** No
- **Published:** 6 Feb 2026
- **Updated:** 9 Feb 2026
- **Also known as:** GHSA-rw25-98wq-76qv

## What is CVE-2026-25647?

CVE-2026-25647 is a medium-severity cross-site scripting vulnerability in B3log Siyuan, published on 6 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.

### Official description

Lute is a structured Markdown engine supporting Go and JavaScript. Lute 1.7.6 and earlier (as used in SiYuan before) has a Stored Cross-Site Scripting (XSS) vulnerability in the Markdown rendering engine. An attacker can inject malicious JavaScript into a Markdown text/note. When another user clicks the rendered content, the script executes in the context of their session.

Weakness: CWE-79 (Improper Neutralization of Input During Web Page Generation)

## Which versions are affected by CVE-2026-25647?

It affects 1 product.


Products: B3log Siyuan.

## How do I fix CVE-2026-25647?

No fix has been published for CVE-2026-25647 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-25647 being exploited?

There is no known exploitation of CVE-2026-25647 in the wild and no public exploit code.

## Other vulnerabilities in B3log Siyuan

- [CVE-2026-32938](https://insights.sbomify.com/CVE-2026-32938/): SiYuan has an Arbitrary File Read in its Desktop Publish Service (critical 9.9)
- [CVE-2026-33669](https://insights.sbomify.com/CVE-2026-33669/): SiYuan has Arbitrary Document Reading within the Publishing Service (critical 9.8)
- [CVE-2026-33670](https://insights.sbomify.com/CVE-2026-33670/): SiYuan has directory traversal within its publishing service (critical 9.8)
- [CVE-2026-32767](https://insights.sbomify.com/CVE-2026-32767/): SiYuan: Authorization Bypass Allows Arbitrary SQL Execution via Search API (critical 9.8)
- [CVE-2024-53504](https://insights.sbomify.com/CVE-2024-53504/): SQL injection in n/a (critical 9.8)

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-25647 and fix it if it is affected.

What it is: CVE-2026-25647 is a medium-severity cross-site scripting vulnerability in B3log Siyuan, published on 6 Feb 2026. Any signed-in user can exploit it over the network, and only if a user opens a file or follows a link.
Exploitation: There is no known exploitation of CVE-2026-25647 in the wild and no public exploit code.

Affected product: B3log Siyuan. No package-level version data is available, so check the vendor advisory linked from the reference page.

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-25647/ (Markdown: https://insights.sbomify.com/CVE-2026-25647/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-25647
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-25647
- OSV: https://osv.dev/vulnerability/CVE-2026-25647

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-25647/
Summaries are generated and may contain mistakes; the official description above is the record.