CVE-2026-4983
4.1 · MEDIUMOverview
CVE-2026-4983 is a medium-severity vulnerability affecting eclipse open_vsx. It was published on June 23, 2026 and has a CVSS 3.1 base score of 4.1 (MEDIUM).
This vulnerability has a CVSS 3.1 base score of 4.1, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
Technical 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.
Remediation
Check the references section for vendor advisories and patches from eclipse. Update open_vsx to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
Affected Products
| Vendor | Product | Versions | Status |
|---|---|---|---|
| eclipse | open_vsx | >= 0.1.0, < 0.34.1 | Affected |
Frequently Asked Questions
What is CVE-2026-4983?
CVE-2026-4983 is a medium-severity vulnerability affecting eclipse open_vsx. It was published on June 23, 2026 and has a CVSS 3.1 base score of 4.1 (MEDIUM).
How severe is CVE-2026-4983?
This vulnerability has a CVSS 3.1 base score of 4.1, rated MEDIUM. It can be exploited remotely over the network. Some level of privileges is required for exploitation.
How do I fix or remediate CVE-2026-4983?
Check the references section for vendor advisories and patches from eclipse. Update open_vsx to the latest patched version. If immediate patching is not possible, review the CVSS vector to understand the attack surface and apply compensating controls such as network segmentation or access restrictions.
How can CyberStrike help with CVE-2026-4983?
CyberStrike's AI-powered security agents can automatically detect CVE-2026-4983 across your infrastructure using autonomous pentesting, DAST scanning, and HackBrowser. The platform continuously monitors for known vulnerabilities and provides actionable remediation guidance prioritized by real-world exploitability.
How CyberStrike Helps
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