Path Traversal in Eclipse Foundation Theia

CVE-2026-12609

In Eclipse Theia versions 1.66.0 and up until including 1.73.1, the `@theia/plugin-ext` backend exposes the `/hostedPlugin/:pluginId/:path(*)` HTTP endpoint, which resolves the requested file path with `path.resolve(localPath, filePath)` w…

Vulnerability class: Path Traversal (Directory Traversal)

CVSS v3 metric

CVSS v3 base score 7.5 (High). Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N.

Affected products

Weakness classification (CWE)

References

Frequently asked questions

What is CVE-2026-12609?
CVE-2026-12609 is a high-severity vulnerability in Eclipse Foundation Theia, classified under Path Traversal. CVSS score: 7.5/10. Published 2026-08-05.
How severe is CVE-2026-12609?
High severity. CVSS v3 base score is 7.5 out of 10.