CVE-2026-46580: High severity Eclipse Foundation Eclipse Theia vulnerability
In Eclipse Theia versions prior to 1.71.0, files matching the pattern .prompts/.prompttemplate in a workspace were automatically loaded and could override or extend the AI agent's system prompts. An attacker could craft a malicious repository containing prompt template files that, when the workspace was opened in Theia, replaced the AI's system instructions with attacker-controlled content (indirect prompt injection). Combined with other AI chat features available in untrusted workspaces, this enabled attack chains leading to data exfiltration via Markdown image rendering or arbitrary command execution via task definitions.
Affected Software
Remediation
Event History
Frequently Asked Questions
What is the severity of CVE-2026-46580?
CVE-2026-46580 has a high severity rating of 8.4 according to the CVSS.
How do I fix CVE-2026-46580?
To fix CVE-2026-46580, update Eclipse Theia to version 1.71.0 or later, where a patch is available.
What does CVE-2026-46580 affect?
CVE-2026-46580 affects Eclipse Theia versions prior to 1.71.0 and its related npm packages that handle AI functionalities.
What can an attacker do with CVE-2026-46580?
An attacker can craft a malicious repository containing prompt template files that could override the AI agent's system prompts in a vulnerable workspace.
When was CVE-2026-46580 published?
CVE-2026-46580 was published on June 18, 2026.