CVE-2026-60009
Eclipse Theia Arbitrary File Write Vulnerability
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.
INFO
Published Date :
Aug. 5, 2026, 11:16 a.m.
Last Modified :
Aug. 7, 2026, 3:54 p.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | HIGH | e51fbebd-6053-4e49-959f-1b94eeb69a2c | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | MITRE-CVE |
Solution
- Update Eclipse Theia to version 1.74.0 or later.
- Ensure workspace confinement and authentication checks are enforced.
- Validate file write operations for all filesystem paths.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-60009.
| URL | Resource |
|---|---|
| https://github.com/eclipse-theia/theia/security/advisories/GHSA-62f6-wcvg-54h3 | Broken Link |
| https://gitlab.eclipse.org/security/cve-assignment/-/work_items/177 | Vendor Advisory |
| https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/595 | Exploit Mitigation Vendor Advisory |
| https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/595 | Exploit Mitigation Vendor Advisory |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-60009 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-60009
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-60009 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-60009 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Aug. 07, 2026
Action Type Old Value New Value Added CPE Configuration OR *cpe:2.3:a:eclipse:theia:*:*:*:*:*:*:*:* versions up to (excluding) 1.74.0 Added Reference Type Eclipse Foundation: https://github.com/eclipse-theia/theia/security/advisories/GHSA-62f6-wcvg-54h3 Types: Broken Link Added Reference Type Eclipse Foundation: https://gitlab.eclipse.org/security/cve-assignment/-/work_items/177 Types: Vendor Advisory Added Reference Type Eclipse Foundation: https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/595 Types: Exploit, Mitigation, Vendor Advisory Added Reference Type CISA-ADP: https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/595 Types: Exploit, Mitigation, Vendor Advisory -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Aug. 05, 2026
Action Type Old Value New Value Added Reference https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/595 Added SSVC {'id': 'CVE-2026-60009', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'total'}], 'version': '2.0.3', 'timestamp': '2026-08-05T12:36:40.861334Z'} -
New CVE Received by [email protected]
Aug. 05, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Eclipse Foundation', 'product': 'Eclipse Theia', 'versions': [{'status': 'affected', 'version': '0', 'lessThan': '1.74.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Added CWE CWE-352 Added CWE CWE-22 Added CWE CWE-306 Added CWE CWE-73 Added Reference https://github.com/eclipse-theia/theia/security/advisories/GHSA-62f6-wcvg-54h3 Added Reference https://gitlab.eclipse.org/security/cve-assignment/-/work_items/177 Added Reference https://gitlab.eclipse.org/security/vulnerability-reports/-/issues/595