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.
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.
Advisories
No advisories yet.
Fixes
Solution
No solution given by the vendor.
Workaround
No workaround given by the vendor.
References
History
Tue, 23 Jun 2026 14:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| First Time appeared |
Eclipse
Eclipse open Vsx |
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| Vendors & Products |
Eclipse
Eclipse open Vsx |
Tue, 23 Jun 2026 12:30:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Title | Malicious SVG Icons Leading to Stored XSS in Eclipse Open VSX | |
| Metrics |
ssvc
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Tue, 23 Jun 2026 11:45:00 +0000
| Type | Values Removed | Values Added |
|---|---|---|
| Description | 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. | |
| Weaknesses | CWE-79 | |
| References |
| |
| Metrics |
cvssV3_1
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Projects
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Status: PUBLISHED
Assigner: eclipse
Published:
Updated: 2026-06-23T12:03:13.663Z
Reserved: 2026-03-27T12:31:27.749Z
Link: CVE-2026-4983
Updated: 2026-06-23T12:03:09.532Z
No data.
No data.
OpenCVE Enrichment
Updated: 2026-06-23T14:15:04Z
Weaknesses