4.1
MEDIUM CVSS 3.1
CVE-2026-13323
Open VSX Registry Uncontrolled Resource Consumption
Description

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.

INFO

Published Date :

July 1, 2026, 12:16 p.m.

Last Modified :

July 1, 2026, 7:59 p.m.

Remotely Exploit :

Yes !
Affected Products

The following products are affected by CVE-2026-13323 vulnerability. Even if cvefeed.io is aware of the exact versions of the products that are affected, the information is not represented in the table below.

ID Vendor Product Action
1 Eclipse open_vsx
CVSS Scores
The Common Vulnerability Scoring System is a standardized framework for assessing the severity of vulnerabilities in software and systems. We collect and displays CVSS scores from various sources for each CVE.
Score Version Severity Vector Exploitability Score Impact Score Source
CVSS 134c704f-9b21-4f2e-91b3-4a467353bcc0
CVSS 3.1 MEDIUM e51fbebd-6053-4e49-959f-1b94eeb69a2c
CVSS 3.1 MEDIUM [email protected]
Solution
Update Open VSX Registry to 1.0.2 or later to fix XSS and supply chain vulnerabilities.
  • Update Open VSX Registry to version 1.0.2.
  • Ensure response headers include Content-Security-Policy.
  • Implement Content-Disposition: attachment header.
  • Review publisher account registrations.
References to Advisories, Solutions, and Tools

Here, you will find a curated list of external links that provide in-depth information, practical solutions, and valuable tools related to CVE-2026-13323.

URL Resource
https://github.com/eclipse-openvsx/openvsx/pull/1922
https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/485
https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/485
CWE - Common Weakness Enumeration

While CVE identifies specific instances of vulnerabilities, CWE categorizes the common flaws or weaknesses that can lead to vulnerabilities. CVE-2026-13323 is associated with the following CWEs:

Common Attack Pattern Enumeration and Classification (CAPEC)

Common Attack Pattern Enumeration and Classification (CAPEC) stores attack patterns, which are descriptions of the common attributes and approaches employed by adversaries to exploit the CVE-2026-13323 weaknesses.

We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).

Results are limited to the first 15 repositories due to potential performance issues.

The following list is the news that have been mention CVE-2026-13323 vulnerability anywhere in the article.

EPSS is a daily estimate of the probability of exploitation activity being observed over the next 30 days. Following chart shows the EPSS score history of the vulnerability.