CVE-2026-4983

Open VSX Registry does not sanitize SVG files uploaded as extension icons prior to storage, and serves them with Content-Type: image/svg+xml without security headers such as Content-Security-Policy or Content-Disposition: attachment. This allows an attacker to publish an extension with a malicious SVG icon and achieve stored cross-site scripting (XSS) when a user navigates directly to the icon URL. On deployments using local storage, script execution occurs within the Open VSX application origin, enabling session hijacking, authentication token theft, and unauthorized extension publishing. On deployments backed by external storage (such as open-vsx.org with an S3-backed CDN), execution is confined to the storage origin, reducing impact but still permitting phishing attacks and credential harvesting through attacker-crafted pages.

CVSS v3 4.1 MEDIUM

4.1^/10

CVSS v3 : MEDIUM

Vector :

Exploitability : 2.3 / Impact : 1.4

Attack Vector NETWORK

Attack Complexity LOW

Privileges Required LOW

User Interaction REQUIRED

Confidentiality Impact NONE

Integrity Impact LOW

Availability Impact NONE

Scope CHANGED

References

Link	Resource
https://gitlab.eclipse.org/security/cve-assignment/-/work_items/91	Issue Tracking Vendor Advisory Exploit

Configurations

Configuration 1 (hide)

cpe:2.3:a:eclipse:open_vsx:*:*:*:*:*:*:*:*

History

24 Jun 2026, 16:55

Type	Values Removed	Values Added
First Time		Eclipse open Vsx Eclipse
References	~~() https://gitlab.eclipse.org/security/cve-assignment/-/work_items/91 -~~	() https://gitlab.eclipse.org/security/cve-assignment/-/work_items/91 - Issue Tracking, Vendor Advisory, Exploit
CPE		cpe:2.3:a:eclipse:open_vsx::::::::

23 Jun 2026, 12:16

Type	Values Removed	Values Added
New CVE

Information

Published : 2026-06-23 12:16

Updated : 2026-06-24 16:55

NVD link : CVE-2026-4983

Mitre link : CVE-2026-4983

CVE.ORG link : CVE-2026-4983

JSON object : View

Products Affected

eclipse

open_vsx

CWE

CWE-79

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

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