Vulnerability · Published Jan 30, 2026 · Assigned by eclipse
CVE-2026-1699
Critical 10.0
In plain English
A critical-severity security flaw in Eclipse Theia - Website from Eclipse Foundation. Proof-of-concept exploit code is public. The chance it is exploited in the next 30 days is estimated at 0.6% (higher than 46% of all known vulnerabilities). Ready-made attack tooling exists: public proof-of-concept code.
Official description
In the Eclipse Theia Website repository, the GitHub Actions workflow .github/workflows/preview.yml used pull_request_target trigger while checking out and executing untrusted pull request code. This allowed any GitHub user to execute arbitrary code in the repository's CI environment with access to repository secrets and a GITHUB_TOKEN with extensive write permissions (contents:write, packages:write, pages:write, actions:write). An attacker could exfiltrate secrets, publish malicious packages to the eclipse-theia organization, modify the official Theia website, and push malicious code to the repository.
Affected products (as reported)
| Vendor | Product | Versions |
|---|---|---|
| Eclipse Foundation | Eclipse Theia - Website | 0 – before 2fb0cc4bfc372cfaef79feb4eebb6563778b2560 |
Weakness: CWE-829 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:H/I:H/A:H