Goal Reached Thanks to every supporter — we hit 100%!

Goal: 1000 CNY · Raised: 1336 CNY

100%

Buy Us a Coffee

CVE-2026-87811— SiYuan before v3.8.2 Stored XSS via notebook template paths

Quick assessment

Affected

siyuan-note siyuan

Exploitation

No confirmed in-the-wild exploitation; assess based on exposure

Recommended action

Check the vendor advisory and references for a fixed version. If immediate upgrade is impossible, restrict exposure and increase monitoring.

在 v3.8.2 之前的 SiYuan 版本中，持久化的笔记本模板路径会被直接插入到 HTML 输入框（input）的 value 属性中，且未进行适当的属性编码。攻击者可以构造恶意的模板路径，从而突破属性上下文，当受害者打开笔记本配置时执行 JavaScript 代码，进而发起同源 API 请求并操纵应用状态。

CVSS 7.3 · High Updated Sep 09, 2026

Possible ATT&CK Techniques 2 AI

T1059 · Command and Scripting Interpreter T1190 · Exploit Public-Facing Application

Get alerts for future matching vulnerabilities Log in to subscribe

Vulnerability Information

Have questions about the vulnerability? See if Shenlong's analysis helps!

View Shenlong Deep Dive ↗

Although we use advanced large model technology, its output may still contain inaccurate or outdated information.Shenlong tries to ensure data accuracy, but please verify and judge based on the actual situation.

Vulnerability Title

SiYuan before v3.8.2 Stored XSS via notebook template paths

Source: CVE Program / CVE List V5

Vulnerability Description

SiYuan before v3.8.2 inserts persisted notebook template paths into HTML input value attributes without proper attribute encoding. Attackers can craft malicious template paths that break out of the attribute context and execute JavaScript when a victim opens notebook configuration, enabling same-origin API requests and application state manipulation.

Source: CVE Program / CVE List V5

CVSS Information

CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:U/C:H/I:H/A:N

Source: CVE Program / CVE List V5

Vulnerability Type

在Web页面生成时对输入的转义处理不恰当(跨站脚本)

Source: CVE Program / CVE List V5

Affected Products

Vendor	Product	Affected Versions	CPE	Subscribe
siyuan-note	siyuan	0 ~ 3.8.2	-

II. Public POCs for CVE-2026-87811

#	POC Description	Source Link	Shenlong Link

AI-Generated POC Premium

No public POC found.

III. Intelligence Information for CVE-2026-87811

请登录查看更多情报信息。

Vendor Advisories for CVE-2026-87811 (2)

🔗 Stored XSS in notebook configuration via unescaped template paths · Advisory · siyuan-note/siyuan · GitHub Read full article vendor-advisory
🔗 SiYuan before v3.8.2 Stored XSS via notebook template paths | Advisories | VulnCheck third-party-advisory

https://www.cve.org/CVERecord?id=CVE-2026-87811

Same Patch Batch · siyuan-note · 2026-09-09 · 9 CVEs total

CVE-2026-87815	8.7 HIGH	SiYuan before v3.8.2 Path Traversal via removeRiffDeck
CVE-2026-87807	7.5 HIGH	siyuan before v3.8.2 SQL Injection via fullTextSearchBlock
CVE-2026-87814	7.3 HIGH	SiYuan before v3.8.2 Stored XSS via Asset Preview
CVE-2026-87813	7.3 HIGH	SiYuan before v3.8.2 Stored XSS via unescaped asset filenames
CVE-2026-87812	6.8 MEDIUM	SiYuan before v3.8.2 Stored XSS via Bazaar iconURL
CVE-2026-87809	6.5 MEDIUM	Siyuan before v3.8.2 Information Disclosure via Export Preview
CVE-2026-87810	5.3 MEDIUM	Siyuan before v3.8.2 Information Disclosure via fullTextSearchBlock
CVE-2026-87808	4.9 MEDIUM	SiYuan before v3.8.2 Read-Only Boundary Bypass via fullTextSearchBlock

IV. Related Vulnerabilities

Same product: siyuan

Same vendor: siyuan-note

Same weakness: CWE-79

V. Comments for CVE-2026-87811

No comments yet

Goal Reached Thanks to every supporter — we hit 100%!

CVE-2026-87811— SiYuan before v3.8.2 Stored XSS via notebook template paths

Quick assessment

Possible ATT&CK Techniques 2 AI

I. Basic Information for CVE-2026-87811

Vulnerability Information

Vulnerability Title

Vulnerability Description

CVSS Information

Vulnerability Type

Affected Products

II. Public POCs for CVE-2026-87811

III. Intelligence Information for CVE-2026-87811

Vendor Advisories for CVE-2026-87811 (2)

Same Patch Batch · siyuan-note · 2026-09-09 · 9 CVEs total

IV. Related Vulnerabilities

V. Comments for CVE-2026-87811

Leave a comment