Flowise versions up to 2.2.4 contain a flaw in the /api/v1/attachments endpoint that allows attackers to upload files without authentication when storageType is set to local. By providing specially crafted values for the chatId and chatflowId parameters, an attacker can exploit a path‑traversal vulnerability to place files in arbitrary directories on the host. This uncontrolled write capability can lead to remote code execution and full server compromise if a malicious payload is uploaded to a directory used by the application or system binaries.

The vulnerability is present in Flowise 2.2.4 and earlier when operating with local storage. No specific product version beyond 2.2.4 was enumerated, so all installations running 2.2.4 or prior with local storage are affected. The CVE references include advisories that confirm the issue, but no additional vendor or patch version information is supplied in the CNA data.

The CVSS score of 9.3 indicates a high severity impact. EPSS is not available, so the precise exploitation probability cannot be quantified, and the vulnerability is not listed in CISA KEV. The attack vector is inferred from the description: unauthenticated access to an endpoint that accepts file uploads combined with a path‑traversal flaw, which would allow an attacker to write files anywhere on the file system. If an attacker uploads a script or binary and places it in an executable location, remote code execution can be achieved, resulting in full server compromise.