CVE-2026-13323

In Open VSX Registry before 1.0.2, the /vscode/unpkg/ endpoint serves user-supplied HTML files with Content-Type: text/html and without a Content-Security-Policy or Content-Disposition: attachment response header. An unauthenticated attacker can register a publisher account, upload a VSIX containing a crafted HTML payload, and induce an authenticated user to visit the resulting URL. The browser renders the file inline in the open-vsx.org origin context, enabling session token exfiltration, persistent Personal Access Token (PAT) generation, and unauthorized publication of malicious extension versions. Because Open VSX extensions are distributed to VS Code, VSCodium, Cursor, Windsurf, and compatible editors, a compromised extension update constitutes a supply chain attack against all downstream users.

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://github.com/eclipse-openvsx/openvsx/pull/1922	Issue Tracking Patch
https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/485	Exploit Issue Tracking Vendor Advisory
https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/485	Exploit Issue Tracking Vendor Advisory

Configurations

Configuration 1 (hide)

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

History

No history.

Information

Published : 2026-07-01 12:16

Updated : 2026-07-06 20:33

NVD link : CVE-2026-13323

Mitre link : CVE-2026-13323

CVE.ORG link : CVE-2026-13323

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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