High 7.5Published Aug 5, 2026

CVE-2026-61891In Eclipse Theia versions up to and including 1.73.1, the `@theia/filesystem` backend exposes HTTP file-download endpoints (`GET /file`, `GET /files/`, `PUT /files/`) that convert a client-supplied U…

Updated under an hour ago (Oct 26, 2026, 7:00 AM ET)

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Every CVE for Eclipse Foundation Eclipse Theia

Exploited in the last 30 days

In Eclipse Theia versions up to and including 1.73.1, the `@theia/filesystem` backend exposes HTTP file-download endpoints (`GET /file`, `GET /files/`, `PUT /files/`) that convert a client-supplied URI directly to a filesystem path and stream the file, without confining it to the workspace or any allow-listed root. 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, so these endpoints are reachable without a valid token. As a result an unauthenticated client can read any file readable by the backend process, including files outside the opened workspace (for example `/etc/hosts`, SSH keys, or tokens). Electron mode uses a separate `ElectronSecurityToken` and is not affected via this path.

CVSS: 7.5 HIGH (v3.1, CNA)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:N/A:N
Weakness (CWE): CWE-22, CWE-36, CWE-200, CWE-306
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: eclipse
NVD analysis: Analyzed
Record last updated: Aug 5, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

Eclipse Foundation Eclipse Theia eclipse_foundation:eclipse_theia (from the name)	before 1.74.0	CNA record
eclipse theia eclipse:theia	before 1.74.0	NVD

References

https://github.com/eclipse-theia/theia/security/advisories/GHSA-qqc8-9538-25v4broken-link
https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/570issue-tracking, vendor-advisory
https://gitlab.eclipse.org/security/cve-assignment/-/work_items/176vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.