Trilium Notes up to 0.103.0 Share Renderer webViewSrc cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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3.5$0-$5k0.30+

Summaryinfo

A vulnerability marked as problematic has been reported in Trilium Notes up to 0.103.0. This affects an unknown function of the component Share Renderer. The manipulation of the argument webViewSrc leads to cross site scripting. This vulnerability is documented as CVE-2026-91021. The attack can be initiated remotely. There is not any exploit available.

Detailsinfo

A vulnerability was found in Trilium Notes up to 0.103.0. It has been rated as problematic. This issue affects an unknown code of the component Share Renderer. The manipulation of the argument webViewSrc 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. The summary by CVE is:

Trilium Notes, version v0.103.0 and earlier, contains a stored cross-site scripting (XSS) vulnerability in the share renderer for webView notes due to improper HTML escaping of user-controlled #webViewSrc values. This vulnerability allows attackers with note-authoring privileges to inject arbitrary JavaScript that executes for any user who opens the shared note, including administrators.

It is possible to read the advisory at vokecyber.com. The identification of this vulnerability is CVE-2026-91021 since 09/14/2026. The exploitation is known to be easy. The attack may be initiated remotely. It demands that the victim is doing some kind of user interaction. Technical details of the vulnerability are known, but there is no available exploit. The attack technique deployed by this issue is T1059.007 according to MITRE ATT&CK.

There is no information about possible countermeasures known. It may be suggested to replace the affected object with an alternative product.

Be aware that VulDB is the high quality source for vulnerability data.

Productinfo

Vendor

Name

Version

CPE 2.3info

CPE 2.2info

CVSSv4info

VulDB Vector: 🔒
VulDB Reliability: 🔍

CVSSv3info

VulDB Meta Base Score: 3.5
VulDB Meta Temp Score: 3.5

VulDB Base Score: 3.5
VulDB Temp Score: 3.5
VulDB Vector: 🔒
VulDB Reliability: 🔍

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
Price Prediction: 🔍
Current Price Estimation: 🔒

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Threat Intelligenceinfo

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

Countermeasuresinfo

Recommended: no mitigation known
Status: 🔍

0-Day Time: 🔒

Timelineinfo

09/14/2026 Advisory disclosed
09/14/2026 +0 days CVE reserved
09/14/2026 +0 days VulDB entry created
09/14/2026 +0 days VulDB entry last update

Sourcesinfo

Advisory: vokecyber.com
Status: Not defined

CVE: CVE-2026-91021 (🔒)
GCVE (CVE): GCVE-0-2026-91021
GCVE (VulDB): GCVE-100-403631

Entryinfo

Created: 09/14/2026 19:37
Changes: 09/14/2026 19:37 (53)
Complete: 🔍
Cache ID: 216::103

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