A path traversal flaw exists in the SendMessageRequest routine of the Send API endpoint in whatsapp-mcp 0.0.1. The vulnerability is triggered by supplying a specially crafted mediaPath argument, which allows the attacker to dereference directories outside the intended media storage location. As a result, an unauthenticated user could read, download, or potentially modify arbitrary files on the server filesystem. This compromise impacts confidentiality and could lead to denial of service or further exploitation if executable files are accessed. The weakness is classified as CWE‑22, reflecting improper validation of path components.

The affected system is the LHarries‑mcp 0.0.1 component. No other versions are listed in the CNA data. Organizations running this exact version of the open‑source project must assess their deployment for exposure to the Send API endpoint.

The CVSS score of 5.1 indicates moderate severity. EPSS information is not available, and the vulnerability is not listed in CISA KEV. The publicly disclosed exploit suggests that the flaw can be used by an attacker who can send requests to the Send API endpoint, implying a remote, network‑based attack vector, though the description does not explicitly state authentication requirements, so the impact may be limited to unauthenticated or authenticated API users. Given the lack of a high base score but public exploitation, operators should consider the risk of unauthorized file access in their threat models.