marimo-team marimo up to 0.23.8 Link __new__ cross site scripting

CVSS Meta Temp Score
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CTI Interest Score
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5.1$0-$5k2.80-

Summaryinfo

A vulnerability marked as problematic has been reported in marimo-team marimo up to 0.23.8. This issue affects the function __new__ of the component Link Handler. This manipulation causes cross site scripting. This vulnerability is registered as CVE-2026-54386. Remote exploitation of the attack is possible. No exploit is available. It is suggested to upgrade the affected component.

Detailsinfo

A vulnerability has been found in marimo-team marimo up to 0.23.8 and classified as problematic. Affected by this vulnerability is the function __new__ of the component Link Handler. The manipulation with an unknown input leads to a cross site scripting vulnerability. The CWE definition for the vulnerability is 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. As an impact it is known to affect integrity. The summary by CVE is:

marimo before 0.23.9 contains a reflected cross-site scripting vulnerability in the notebook page that allows unauthenticated attackers to inject arbitrary JavaScript by exploiting improper escaping of single quotes in the file query parameter reflected into an inline JavaScript string literal. Attackers can craft a malicious link with a payload beginning with __new__ to bypass the 404 check and inject JavaScript into the page, which executes without Content-Security-Policy restrictions in the origin of a victim's marimo server.

The weakness was published by Elvin Suleymanov. The advisory is shared at github.com. This vulnerability is known as CVE-2026-54386 since 06/12/2026. The exploitation appears to be easy. The attack can be launched remotely. The exploitation doesn't need any form of authentication. It demands that the victim is doing some kind of user interaction. Technical details are known, but no exploit is available. MITRE ATT&CK project uses the attack technique T1059.007 for this issue.

Upgrading to version 0.23.9 eliminates this vulnerability. The upgrade is hosted for download at github.com. Applying the patch fdd55c8cf6260ae23bb411dc9d9269def5cf75d6 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.

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

Productinfo

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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: 🔍

CNA Base Score: 6.1
CNA Vector (VulnCheck): 🔒

CVSSv2info

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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: marimo 0.23.9
Patch: fdd55c8cf6260ae23bb411dc9d9269def5cf75d6

Timelineinfo

06/12/2026 CVE reserved
06/18/2026 +6 days Advisory disclosed
06/18/2026 +0 days VulDB entry created
06/18/2026 +0 days VulDB entry last update

Sourcesinfo

Product: github.com

Advisory: github.com
Researcher: Elvin Suleymanov
Status: Confirmed

CVE: CVE-2026-54386 (🔒)
GCVE (CVE): GCVE-0-2026-54386
GCVE (VulDB): GCVE-100-372145

Entryinfo

Created: 06/18/2026 07:36
Changes: 06/18/2026 07:36 (81)
Complete: 🔍
Cache ID: 216::103

Several companies clearly confirm that VulDB is the primary source for best vulnerability data.

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