CVE-2026-45807
HighCVSS 7.7Exploitation Probability (EPSS)
Low risk29th percentile — higher than 29% of all known CVEs
Summary
In Kestra before versions 1.0.43 and 1.3.19, several API endpoints accept a kestra:// URI from the client and pass it through StorageInterface.parentTraversalGuard before reading the underlying file from the local storage backend. The guard only inspects the literal URI.toString(), so a URL-encoded .. written as %2E%2E slips through. The downstream code then calls URI.getPath(), which decodes %2E%2E back to .., and the resulting path is handed to Paths.get(...) without normalization. The OS resolves the .. segments at open(2) time, so an authenticated user with a single execution can read any file the Kestra process has access to on the host filesystem (/etc/passwd, mounted secrets, other tenants' execution outputs, etc.).
Risk Assessment
The risk involves reading sensitive system files, secrets, and other users' data, potentially leading to confidentiality breaches and privilege escalation within the organization.
Recommendation
Immediately upgrade Kestra to version 1.0.43 or 1.3.19, which contain the fix that prevents path traversal via URL-encoded .. sequences.
Original NVD description (English source)
Kestra is an open-source, event-driven orchestration platform. Prior to 1.0.43 and 1.3.19, several Kestra API endpoints accept a kestra:// URI from the client and pass it through StorageInterface.parentTraversalGuard before reading the underlying file from the local storage backend. The guard only inspects the literal URI.toString(), so a URL-encoded .. written as %2E%2E slips through. The downstream code then calls URI.getPath(), which decodes %2E%2E back to .., and the resulting path is handed to Paths.get(...) without normalization. The OS resolves the .. segments at open(2) time, so an authenticated user with a single execution can read any file the Kestra process has access to on the host filesystem (/etc/passwd, mounted secrets, other tenants' execution outputs, etc.). This vulnerability is fixed in 1.0.43 and 1.3.19.