CVE-2026-13445 is an authorization bypass vulnerability in IBM Langflow OSS (versions 1.0.0 through 1.10.1) involving the SaveToFile component. Authenticated attackers can exploit this by specifying absolute paths to victim storage locations, enabling them to read and modify files belonging to other users. In append mode, attackers read victim file contents and append attacker-controlled data, uploading a copy to their namespace, resulting in confidentiality compromise. In overwrite mode, attackers can replace victim files with arbitrary data, causing integrity violations. This vulnerability violates storage ownership boundaries and requires authenticated access.

The vulnerability allows authenticated attackers to breach confidentiality by reading other users' files and to breach integrity by modifying or overwriting those files. This compromises data isolation between users and can lead to unauthorized data disclosure and tampering within IBM Langflow OSS environments.

Patch status is not yet confirmed — check the vendor advisory for current remediation guidance. Until an official fix is available, restrict access to trusted authenticated users only and monitor for suspicious file access patterns related to the SaveToFile component. Avoid using absolute paths in workflows if possible.