CVE-2026-87812 PUBLISHED

SiYuan before v3.8.2 Stored XSS via Bazaar iconURL

Assigner: VulnCheck
Reserved: 09.09.2026 Published: 09.09.2026 Updated: 09.09.2026

SiYuan before v3.8.2 contains a stored cross-site scripting vulnerability in Bazaar package cards where the iconURL metadata is inserted directly into HTML img src attributes without escaping. Attackers can inject malicious URLs with event handlers that execute JavaScript in the authenticated SiYuan origin when users view Bazaar listings, enabling API requests and application state manipulation.

CVSS Vector: CVSS:4.0/AV:N/AC:L/AT:P/PR:N/UI:A/VC:H/VI:H/VA:N/SC:N/SI:N/SA:N
CVSS Score: 7.4

Exploitability Metrics		Vulnerable System Impact Metrics		Subsequent System Impact Metrics
Attack Vector	Network	Confidentiality	High	Confidentiality	None
Attack Complexity	Low	Integrity	High	Integrity	None
Attack Requirements	Present	Availability	None	Availability	None
Privileges Required	None
User Interaction	Active

CVSS 4.0

CVSS Vector: CVSS:3.1/AV:N/AC:H/PR:N/UI:R/S:U/C:H/I:H/A:N
CVSS Score: 6.8

Attack Vector	Network	Scope	Unchanged
Attack Complexity	High	Confidentiality Impact	High
Privileges Required	None	Integrity Impact	High
User Interaction	Required	Availability Impact	None

CVSS 3.1

Product Status

Vendor	siyuan-note
Product	siyuan
Versions	Default: unaffected affected from 0 to 3.8.2 (excl.) Version 3.8.2 is unaffected

References

Problem Types

Improper Neutralization of Input During Web Page Generation ('Cross-site Scripting') CWE