SB2026072287 - Multiple vulnerabilities in Eclipse Theia
Published: July 22, 2026
Breakdown by Severity
- Low
- Medium
- High
- Critical
Description
This security bulletin contains information about 2 vulnerabilities.
1) Server-Side Request Forgery (SSRF) (CVE-ID: CVE-2026-10055)
CWE-ID: CWE-918 - Server-Side Request Forgery (SSRF)
CVSSv4: 7.1 [CVSS:4.0/AV:N/AC:L/AT:N/PR:L/UI:N/VC:H/VI:L/VA:N/SC:L/SI:N/SA:N]
The vulnerability allows a remote user to send server-side requests to internal or localhost endpoints and disclose sensitive response data.
The vulnerability exists due to server-side request forgery in the /services/request-service RPC when handling an attacker-controlled URL through the standard /services messaging endpoint. A remote user can invoke the RPC with a crafted URL to send server-side requests to internal or localhost endpoints and disclose sensitive response data.
The full response body is returned to the caller base64-encoded, and the issue is reachable through the standard frontend/backend connection without special configuration for the affected RPC.
2) Missing Origin Validation in WebSockets (CVE-ID: CVE-2026-10054)
CWE-ID: CWE-1385 - Missing Origin Validation in WebSockets
CVSSv4: 8.4 [CVSS:4.0/AV:L/AC:L/AT:N/PR:N/UI:A/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N]
The vulnerability allows a remote attacker to execute arbitrary commands and read their output.
The vulnerability exists due to missing origin validation in WebSocket terminal RPC services when handling cross-origin WebSocket connections. A remote attacker can lure a victim into visiting a malicious webpage that connects to the terminal service and issues crafted terminal RPC requests to execute arbitrary commands and read their output.
User interaction is required to visit a malicious webpage, and the issue affects browser-based deployments where the backend WebSocket is reachable.
Remediation
Install update from vendor's website.