CVE-2026-60009
The handler takes an attacker-supplied absolute path from the multipart `uri` field and calls `fs.move(tmp, target, { overwrite: true })` with no workspace confinement and no authentication.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.37%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
In Eclipse Theia versions up to and including 1.73.1, the `@theia/filesystem` backend binds `POST /file-upload` in every filesystem-enabled deployment. The handler takes an attacker-supplied absolute path from the multipart `uri` field and calls `fs.move(tmp, target, { overwrite: true })` with no workspace confinement and no authentication. In browser (non-Electron) deployments the connection token is enforced only on WebSocket upgrades; the HTTP middleware in `@theia/core` re-issues the cookie and calls `next()` without rejecting tokenless HTTP requests. Because `multipart/form-data` is a CORS-safelisted request type, a cross-origin web page can trigger the write with no preflight and no credentials, resulting in an unauthenticated arbitrary file write outside the workspace to any absolute path the backend process can write. This can escalate to remote code execution, for example by overwriting a startup-executed file such as `~/.bashrc`. Electron mode uses a separate `ElectronSecurityToken` and is not affected via this path.
- CVSS 3.1
- 8.8 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H
- EPSS
- 0.37% probability · 30th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-22, CWE-73, CWE-306, CWE-352
- Affected
- eclipse/theia
- Source
- emo@eclipse.org
References
- https://github.com/eclipse-theia/theia/security/advisories/GHSA-62f6-wcvg-54h3Broken Link
- https://gitlab.eclipse.org/security/cve-assignment/-/work_items/177Vendor Advisory
- https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/595Exploit, Mitigation, Vendor Advisory
- https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/595Exploit, Mitigation, Vendor Advisory
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.