CVE-2026-13323 (GCVE-0-2026-13323)

Vulnerability from cvelistv5 – Published: 2026-07-01 11:28 – Updated: 2026-07-01 12:19
VLAI
Summary
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.
Severity
4.1 (Medium)
CVSS:3.1/AV:N/AC:L/PR:L/UI:R/S:C/C:N/I:L/A:N
SSVC
Exploitation: none Automatable: no Technical Impact: partial
CISA Coordinator · CISA-ADP (v2.0.3)
Decision recorded 2026-07-01 12:13 UTC
CWE
  • CWE-79 - Improper neutralization of input during web page generation ('cross-site scripting')
Assigner
eclipse CNA under the mitre root
CNA scorecard C 66/100 over 217 records in the last 180 days details
References
Impacted products
Vendor Product Version CPE status
Eclipse Foundation Eclipse Open VSX Affected: 0.1.0 , < 1.0.2 (semver)
guessed Create a notification for this product.
Credits
Golan Myers
Show details on NVD website
To clipboard 

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