CVE-2026-31809

Published: Mar 10, 2026 Last Modified: Mar 11, 2026
ExploitDB:
Other exploit source:
Google Dorks:
MEDIUM 6,4
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: passive
Confidentiality: N/A
Integrity: N/A
Availability: N/A
MEDIUM 6,1
Source: [email protected]
Attack Vector: network
Attack Complexity: low
Privileges Required: none
User Interaction: required
Scope: changed
Confidentiality: low
Integrity: low
Availability: none

Description

AI Translation Available

SiYuan is a personal knowledge management system. Prior to 3.5.10, SiYuan's SVG sanitizer (SanitizeSVG) checks href attributes for the javascript: prefix using strings.HasPrefix(). However, inserting ASCII tab (	), newline (
), or carriage return (
) characters inside the javascript: string bypasses this prefix check. Browsers strip these characters per the WHATWG URL specification before parsing the URL scheme, so the JavaScript still executes. This allows an attacker to inject executable JavaScript into the unauthenticated /api/icon/getDynamicIcon endpoint, creating a reflected XSS. This is a second bypass of the fix for CVE-2026-29183 (fixed in v3.5.9). This vulnerability is fixed in 3.5.10.

EPSS (Exploit Prediction Scoring System)

Trend Analysis

EPSS (Exploit Prediction Scoring System)

Prevede la probabilità di sfruttamento basata su intelligence sulle minacce e sulle caratteristiche della vulnerabilità.

EPSS Score
0,0003
Percentile
0,1th
Updated

EPSS Score Trend (Last 7 Days)

79

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

Stable
Abstraction: Base Structure: Simple
Common Consequences
Security Scopes Affected:
Access Control Confidentiality Integrity Availability
Potential Impacts:
Bypass Protection Mechanism Read Application Data Execute Unauthorized Code Or Commands
Applicable Platforms
Technologies: AI/ML, Web Based, Web Server
Likelihood of Exploit: High
View CWE Details
Application

Siyuan by B3Log

Product Information
Vendor B3Log
Product Siyuan
Version Range Affected
To 3.5.10 (exclusive)
cpe:2.3:a:b3log:siyuan:*:*:*:*:*:*:*:*
Common Platform Enumeration - Standardized vulnerability identification
https://github.com/siyuan-note/siyuan/security/advisories/G…
https://github.com/siyuan-note/siyuan/security/advisories/GHSA-pmc9-f5qr-2pcr