CVE-2026-19884: eclipse foundation eclipse theia

Vulnerability summary

CVE-2026-19884 is a high (CVSS 8.4) vulnerability in eclipse foundation eclipse theia. EPSS estimates a 0.23% chance of exploitation in the next 30 days, higher than 12.7% of scored vulnerabilities.

Timeline

1. 14-08-2026
   PublishedVulnerability first disclosed.
2. 17-08-2026
   Last modifiedVulnerability information updated.

Description

In Eclipse Theia versions up to and including 1.69.0, opening a folder starts source control integration without requiring the user to trust the folder first. This affects applications built on Theia that include the git integration, such as the Theia IDE. Both Theia's own `@theia/git` extension and the builtin VS Code `git` extension run git commands such as `git status` as soon as a repository is detected. Since git honors repository-local configuration, a folder containing an attacker-controlled `.git/config` with `core.fsmonitor` (or a comparable hook-like setting) causes the configured command to be executed. The configuration can be delivered by burying a bare repository inside a regular repository (OVE-20210718-0001), so cloning an attacker-supplied repository and opening it in a Theia-based application is sufficient to execute arbitrary commands with the privileges of the user, without any confirmation prompt. As of 1.70.0, plugins that declare `capabilities.untrustedWorkspaces.supported: false`, which includes the builtin git extension, are no longer loaded or activated in an untrusted workspace, and the deprecated `@theia/git` extension has been removed, so no git command is executed against an untrusted folder.

• CWE-15External Control of System or Configuration SettingOne or more system settings or configuration elements can be externally controlled by a user.
• CWE-829Inclusion of Functionality from Untrusted Control SphereThe product imports, requires, or includes executable functionality (such as a library) from a source that is outside of the intended control sphere.