CVE-2026-45807 HIGH

CVE-2026-45807: Kestra: Path traversal via URL-encoded "%2E%2E" in execution and namespace file endpoints allows arbitrary file read

Vendor Kestra-Io
Product kestra
Weakness CWE-22 · Path traversal
Published June 26, 2026
Last update June 29, 2026

CVSS base score

7.7/10
Attack vector Network
Attack complexity Low
Privileges required Low
User interaction None
Confidentiality High
Integrity None

CVSS vector

CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:C/C:H/I:N/A:N

What the vulnerability does

01Description

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.

Key dates

02Disclosure timeline

June 26, 2026 CVE published
June 29, 2026 Record updated