Open VSX Registry <1.0.2 XSS/CSRF via /vscode/unpkg/ no CSP
CVE-2026-13323 Published on July 1, 2026
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.
Vulnerability Analysis
CVE-2026-13323 can be exploited with network access, requires user interaction and a small amount of user privileges. This vulnerability is considered to have a low attack complexity. The potential impact of an exploit of this vulnerability is considered to have no impact on confidentiality, with no impact on integrity, and no impact on availability.
Weakness Type
What is a XSS Vulnerability?
The software does not neutralize or incorrectly neutralizes user-controllable input before it is placed in output that is used as a web page that is served to other users.
CVE-2026-13323 has been classified to as a XSS vulnerability or weakness.
Products Associated with CVE-2026-13323
Want to know whenever a new CVE is published for Eclipse Open Vsx? stack.watch will email you.
Affected Versions
Eclipse Foundation Eclipse Open VSX:- Version 0.1.0 and below 1.0.2 is affected.