CVE-2026-10055
Eclipse Theia Request Service Server-Side Request Forgery
Description
In Eclipse Theia since version 1.26.0, the backend /services/request-service RPC accepts an attacker-controlled URL from any client connected to the standard /services messaging endpoint, performs the HTTP request server-side, and returns the full response body to the caller. Because the destination URL is neither validated nor allowlisted, a remote attacker with access to the Theia service connection can issue server-side HTTP requests to localhost or other backend-reachable hosts and read their responses, exposing internal administrative endpoints, cloud instance metadata services, and other resources that are intentionally outside the browser network boundary. The vulnerability affects deployments where the Theia service connection is reachable by untrusted users (for example, multi-tenant or publicly-reachable Theia deployments).
INFO
Published Date :
July 3, 2026, 11:16 a.m.
Last Modified :
Oct. 25, 2026, 9:10 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] |
Solution
- Update Eclipse Theia to a patched version.
- Validate and allowlist destination URLs.
- Restrict access to the Theia service.
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-2026-10055.
| URL | Resource |
|---|---|
| https://github.com/eclipse-theia/theia/security/advisories/GHSA-2m57-xxmh-v696 | |
| https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/446 |
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-10055 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-2026-10055
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-2026-10055 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-10055 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.
-
CVE Translated by [email protected]
Oct. 25, 2026
Action Type Old Value New Value Added Translation Title: Eclipse Theia de Eclipse Foundation, Description: En Eclipse Theia desde la versión 1.26.0, el RPC de backend /services/request-service acepta una URL controlada por el atacante de cualquier cliente conectado al endpoint de mensajería estándar /services, realiza la solicitud HTTP del lado del servidor y devuelve el cuerpo completo de la respuesta al llamador. Debido a que la URL de destino no es validada ni está en una lista blanca, un atacante remoto con acceso a la conexión del servicio Theia puede emitir solicitudes HTTP del lado del servidor a localhost u otros hosts accesibles desde el backend y leer sus respuestas, exponiendo endpoints administrativos internos, servicios de metadatos de instancias en la nube y otros recursos que están intencionalmente fuera del límite de red del navegador. La vulnerabilidad afecta a las implementaciones donde la conexión del servicio Theia es accesible por usuarios no confiables (por ejemplo, implementaciones de Theia multi-inquilino o accesibles públicamente). -
CVE Modified by 134c704f-9b21-4f2e-91b3-4a467353bcc0
Jul. 06, 2026
Action Type Old Value New Value Added SSVC {'id': 'CVE-2026-10055', 'role': 'CISA Coordinator', 'options': [{'exploitation': 'none'}, {'automatable': 'no'}, {'technicalImpact': 'partial'}], 'version': '2.0.3', 'timestamp': '2026-07-06T15:23:27.971948Z'} -
New CVE Received by [email protected]
Jul. 03, 2026
Action Type Old Value New Value Added Affected [{'vendor': 'Eclipse Foundation', 'product': 'Eclipse Theia', 'versions': [{'status': 'affected', 'version': '1.26.0', 'lessThan': '1.73.0', 'versionType': 'semver'}], 'defaultStatus': 'unaffected'}] Added Description In Eclipse Theia since version 1.26.0, the backend /services/request-service RPC accepts an attacker-controlled URL from any client connected to the standard /services messaging endpoint, performs the HTTP request server-side, and returns the full response body to the caller. Because the destination URL is neither validated nor allowlisted, a remote attacker with access to the Theia service connection can issue server-side HTTP requests to localhost or other backend-reachable hosts and read their responses, exposing internal administrative endpoints, cloud instance metadata services, and other resources that are intentionally outside the browser network boundary. The vulnerability affects deployments where the Theia service connection is reachable by untrusted users (for example, multi-tenant or publicly-reachable Theia deployments). Added CVSS V3.1 AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:L/A:N Added CWE CWE-200 Added CWE CWE-918 Added Reference https://github.com/eclipse-theia/theia/security/advisories/GHSA-2m57-xxmh-v696 Added Reference https://gitlab.eclipse.org/security/vulnerability-reports/-/work_items/446