Vulnerability DatabaseCVE-2026-87811
Mend.io Vulnerability Database
The largest open source vulnerability database
What is a Vulnerability ID?
New vulnerability? Tell us about it!
CVE-2026-87811
Published:September 09, 2026
Updated:September 22, 2026
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.
Affected Packages
https://github.com/siyuan-note/siyuan.git (GITHUB):
Affected version(s) >=v2.0.14 <v3.8.2
Fix Suggestion:
Update to version v3.8.2
Related Resources (3)
https://www.vulncheck.com/advisories/siyuan-before-3.8.2-stored-xss-via-notebook-template-paths
https://nvd.nist.gov/vuln/detail/CVE-2026-87811
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-v6wf-r2gr-rrgf
Do you need more information?
Contact Us
CVSS v4
Base Score:
8.4
Attack Vector
NETWORK
Attack Complexity
LOW
Attack Requirements
NONE
Privileges Required
LOW
User Interaction
ACTIVE
Vulnerable System Confidentiality
HIGH
Vulnerable System Integrity
HIGH
Vulnerable System Availability
NONE
Subsequent System Confidentiality
NONE
Subsequent System Integrity
NONE
Subsequent System Availability
NONE
CVSS v3
Base Score:
7.3
Attack Vector
NETWORK
Attack Complexity
LOW
Privileges Required
LOW
User Interaction
REQUIRED
Scope
UNCHANGED
Confidentiality
HIGH
Integrity
HIGH
Availability
NONE
Weakness Type (CWE)
Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting')
CWE-79
EPSS
Base Score:
0.21