This vulnerability is an integer overflow in the Svc::FileDownlink SendPartial functionality of the F Prime framework, which occurs when a caller supplies a length that, added to a start offset, overflows a 32‑bit unsigned integer. The overflow bypasses file‑range validation, allowing the internal byte offset to become greater than the wrapped end offset; this triggers a FW_ASSERT and causes the process to abort or reset, resulting in a denial of service.

The flaw affects all releases of the F Prime framework before version 4.3.0; any component that processes file‑download requests through SendPartial is potentially vulnerable. The issue is solved in F Prime 4.3.0 and later.

The CVSS score of 6.5 indicates a moderate severity. The EPSS score is expressed as less than 1%, implying a very low but non‑zero exploitation probability. The vulnerability is not listed in the CISA KEV catalog. Based on the description, it is inferred that an attacker who can control the parameters of a SendPartial request—either locally or remotely if the API is exposed—can trigger the DoS by causing the framework to abort or reset.