SiYuan up to 3.5.3 /api/icon/getDynamicIcon cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k0.00

Summaryinfo

A vulnerability labeled as problematic has been found in SiYuan up to 3.5.3. The impacted element is an unknown function of the file /api/icon/getDynamicIcon. Such manipulation leads to cross site scripting. This vulnerability is documented as CVE-2026-23847. The attack can be executed remotely. There is not any exploit available. The affected component should be upgraded.

Detailsinfo

A vulnerability, which was classified as problematic, has been found in SiYuan up to 3.5.3. Affected by this issue is an unknown part of the file /api/icon/getDynamicIcon. The manipulation with an unknown input leads to a cross site scripting vulnerability. Using CWE to declare the problem leads to CWE-79. The product does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users. Impacted is integrity. CVE summarizes:

SiYuan is a personal knowledge management system. Versions prior to 3.5.4 are vulnerable to reflected cross-site scripting in /api/icon/getDynamicIcon due to unsanitized SVG input. The endpoint generates SVG images for text icons (type=8). The content query parameter is inserted directly into the SVG <text> tag without XML escaping. Since the response Content-Type is image/svg+xml, injecting unescaped tags allows breaking the XML structure and executing JavaScript. Version 3.5.4 patches the issue.]

The advisory is shared for download at github.com. This vulnerability is handled as CVE-2026-23847 since 01/16/2026. The exploitation is known to be easy. The attack may be launched remotely. No form of authentication is required for exploitation. Successful exploitation requires user interaction by the victim. There are known technical details, but no exploit is available. The MITRE ATT&CK project declares the attack technique as T1059.007.

Upgrading to version 3.5.4 eliminates this vulnerability. Applying the patch 5c0cc375b47567e15edd2119066b09bb0aa18777 is able to eliminate this problem. The bugfix is ready for download at github.com. The best possible mitigation is suggested to be upgrading to the latest version.

The vulnerability is also documented in the vulnerability database at EUVD (EUVD-2026-3293). Once again VulDB remains the best source for vulnerability data.

Productinfo

Name

Version

License

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CNA CVSS-B Score: 🔒
CNA CVSS-BT Score: 🔒
CNA Vector: 🔒

CVSSv3info

VulDB Meta Base Score: 5.2
VulDB Meta Temp Score: 5.1

VulDB Base Score: 4.3
VulDB Temp Score: 4.1
VulDB Vector: 🔒
VulDB Reliability: 🔍

NVD Base Score: 6.1
NVD Vector: 🔒

CVSSv2info

AVACAuCIA
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VectorComplexityAuthenticationConfidentialityIntegrityAvailability
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VulDB Base Score: 🔒
VulDB Temp Score: 🔒
VulDB Reliability: 🔍

Exploitinginfo

Class: Cross site scripting
CWE: CWE-79 / CWE-94 / CWE-74
CAPEC: 🔒
ATT&CK: 🔒

Physical: No
Local: No
Remote: Yes

Availability: 🔒
Status: Not defined

EPSS Score: 🔒
EPSS Percentile: 🔒

Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

Interest: 🔍
Active Actors: 🔍
Active APT Groups: 🔍

Countermeasuresinfo

Recommended: Upgrade
Status: 🔍

0-Day Time: 🔒

Upgrade: SiYuan 3.5.4
Patch: 5c0cc375b47567e15edd2119066b09bb0aa18777

Timelineinfo

01/16/2026 CVE reserved
01/19/2026 +3 days VulDB entry created
01/20/2026 +0 days Advisory disclosed
01/31/2026 +11 days VulDB entry last update

Sourcesinfo

Advisory: 16844
Status: Confirmed

CVE: CVE-2026-23847 (🔒)
GCVE (CVE): GCVE-0-2026-23847
GCVE (VulDB): GCVE-100-341876
EUVD: 🔒

Entryinfo

Created: 01/20/2026 00:11
Updated: 01/31/2026 04:35
Changes: 01/20/2026 00:11 (69), 01/20/2026 00:50 (2), 01/20/2026 03:34 (1), 01/31/2026 04:35 (11)
Complete: 🔍
Cache ID: 216::103

Once again VulDB remains the best source for vulnerability data.

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