IBM Langflow OSS versions 1.0.0 through 1.10.1 contain a flaw in the SaveToFile component that allows an authenticated attacker to specify absolute file paths in uploaded file operations. The attacker can read other users’ stored files in append mode, or overwrite them with arbitrary data in overwrite mode. This effectively breaks the storage ownership boundary, resulting in confidentiality and integrity compromise of other users' data and potentially exposing sensitive content.

IBM Langflow OSS, impacted versions 1.0.0 to 1.10.1, are affected. The vulnerability is present in the open source implementation distributed via PyPI.

With a CVSS score of 8.1, this vulnerability is considered high severity. The EPSS score is less than 1%, indicating a lower likelihood of exploitation at present, and it is not listed in the CISA KEV catalog. Attackers need only authenticated access to the vulnerable API; no additional privileges or special conditions are required. An attacker can choose absolute paths that point to files owned by other users, leading to direct file read or overwrite operations through the SaveToFile component.