CVE-2025-34120: Limesurvey GmbH Limesurvey

High severity, CVSS 8.7. EPSS: 1.9% chance of exploitation in the next 30 days.

An unauthenticated file download vulnerability exists in LimeSurvey versions from 2.0+ up to and including 2.06+ Build 151014. The application fails to validate serialized input to the admin backup endpoint (`index.php/admin/update/sa/backup`), allowing attackers to specify arbitrary file paths using a crafted `datasupdateinfo` payload. The files are packaged in a ZIP archive and made available for download without authentication. This vulnerability can be exploited to read arbitrary files on the host system, including sensitive OS and configuration files.

Affected products

• Limesurvey GmbH Limesurvey: from 2.0+, up to and including 2.06+ Build 151014

Published 2025-07-16. Last modified 2026-06-17.