AUGUST 15, 2026
Live Feed
Back to database
Case File

CVE-2026-61891

HIGH · CVSS 7.5 EPSS 0.45% Public Exploit

Source: NVD + CISA KEV + EPSS · Published 2026-08-05 · Last synced 2026-08-15

CyberRota Analysis

AI-Generated

Eclipse Theia versions up to 1.73.1 have a vulnerability in the `@theia/filesystem` backend that allows unauthenticated clients to access HTTP file-download endpoints, enabling them to read any file accessible by the backend process, including sensitive files outside the designated workspace. This flaw arises from improper URI handling and insufficient token validation for HTTP requests, posing a significant risk to systems where Theia is deployed in a browser environment. Organizations using affected versions should prioritize remediation to prevent potential data exposure and unauthorized access to sensitive information.

Public Exploit Signal

A public exploit, PoC, GitHub repository or Metasploit reference was detected for this CVE.

GitHub PoC Links

Note: these links are listed for security research and verification purposes only.

CVE
CVE-2026-61891
Severity
HIGH
CVSS
7.5
EPSS
0.45%

Original NVD Description

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.

Related CVEs

Other vulnerabilities affecting the same vendor(s)