CVE-2026-4983 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-4983MEDIUM

Eclipse Foundation Eclipse Open VSX — Open VSX Registry does not sanitize SVG files uploaded as extension icons prior to storage, and serves them with Content-Type: image/svg+…

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   L   R  C  L  L  N    5.4   .0022   13.3     —

AFFECTED
  Product           Versions  Fixed
  Eclipse Open VSX  0.1.0 –   —

TIMELINE
  Mar 27  Reserved by eclipse
  Jun 23  EXPLOIT PUBLISHED — CVE-2026-4983 (Eclipse Foundation Eclipse Open VSX). Public exploit reference added.
  Jun 23  Published (CNA: eclipse)

CWE-79 · CNA: eclipse · CVSS v3.1 · 1 reference · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
March 27, 2026	Reserved	Reserved by eclipse
June 23, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-4983 (Eclipse Foundation Eclipse Open VSX). Public exploit reference added.
June 23, 2026	Published	Published (CNA: eclipse)

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
Eclipse Foundation	Eclipse Open VSX	—	0.1.0	—

Weaknesses

CWE-79

References (1)

https://gitlab.eclipse.org/security/cve-assignment/-/work_items/91 [Issue Tracking, Vendor Advisory, Exploit]

Authoritative record: CVE-2026-4983 at cve.org

Vendors: eclipse foundation

Weaknesses: CWE-79

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-4983 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Wednesday, August 19, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.