CVE-2026-14574 Eclipse Foundation CVE debrief

Who should care

Organizations and developers using Eclipse Theia versions 0.7.0 through 1.73.1 should review and update their installations to prevent potential prototype pollution attacks. This includes reviewing workspace settings files for crafted preference values and monitoring application logic for unexpected changes. Security teams and vulnerability management teams should also be aware of this vulnerability and take necessary steps to mitigate it. Additionally, operators and platform administrators should be aware of the potential impact on their systems and take steps to protect them. This vulnerability can be mitigated by updating to version 1.73.2 or later, verifying workspace settings files, and monitoring application logic for unexpected changes. Compensating controls, such as restricting access to workspace settings files, can also be implemented while remediation is scheduled and verified. Relevant monitoring, detection, and logs should be checked for exposed assets that need extra review. Exceptions should be tracked, and remediated assets should be retested and closed only after evidence is documented. Asset inventory and source tracking can also help in mitigating this vulnerability. Rollback/change windows can be used to minimize the impact of the vulnerability while remediation is being implemented. Overall, a comprehensive approach is needed to mitigate this vulnerability, involving multiple stakeholders and teams. Eclipse Theia's user community and developers should also be aware of this vulnerability and take necessary steps to protect their systems. This requires a coordinated effort from multiple teams and stakeholders to ensure that the vulnerability is properly mitigated. The vulnerability management team should track the remediation progress and verify that the mitigation measures are effective. The security team should also review the configuration and settings of the affected systems to ensure that they are secure. The operators and administrators should be aware of the potential impact on their systems and take steps to protect them. The platform administrators should review the configuration and settings of the affected systems to ensure that они

Technical summary

The `PreferenceUtils.merge` function in `@theia/core` recursively merges preference values without rejecting prototype-related keys. A crafted preference value in a workspace settings file can pollute `Object.prototype` when the user opens the workspace, potentially altering application logic across the Theia process. This vulnerability affects Eclipse Theia versions 0.7.0 through 1.73.1 and can be mitigated by updating to version 1.73.2 or later.

Defensive priority

Organizations using Eclipse Theia versions 0.7.0 through 1.73.1 should review and update their installations to prevent potential prototype pollution attacks.

Recommended defensive actions

• Review and update Eclipse Theia installations to version 1.73.2 or later
• Verify workspace settings files for crafted preference values
• Monitor application logic for unexpected changes
• Confirm whether affected product deployments exist in managed environments and assign an owner for follow-up.
• Review the supplied official advisory or CVE record to validate affected scope, severity, and vendor guidance.
• Plan vendor-supported updates or mitigations through normal change control where exposure is confirmed.
• Check relevant monitoring, detection, and logs for exposed assets that need extra review.

Evidence notes

The CVE record indicates that Eclipse Theia versions 0.7.0 and up to 1.73.1 are affected by a prototype pollution vulnerability due to the `PreferenceUtils.merge` function in `@theia/core`. This function recursively merges preference values without rejecting prototype-related keys. A crafted preference value in a workspace settings file can pollute `Object.prototype` when the user opens the workspace, potentially altering application logic across the Theia process.

Official resources