GHSA-7c47-xr7q-p6hg

free5GC NRF Discovery EncodeGroupId Function Panics on Malformed group-id-list Parameter

**Impact** This is an Improper Input Validation vulnerability leading to Denial of Service. - **Security Impact**: A remote attacker can cause the NRF service to panic and crash by sending a crafted HTTP GET request with a malformed `group-id-list` parameter. This results in complete denial of service for the NRF discovery service. - **Functional Impact**: The `EncodeGroupId` function attempts to access array indices [0], [1], [2] without validating the length of the split data. When the parameter contains insufficient separator characters, the code panics with "index out of range". - **Affected Parties**: All deployments of free5GC v4.0.1 using the NRF discovery service. **Patches** Yes, the issue has been patched. The fix is implemented in PR free5gc/nrf#80 (commit: [add fix reference here]). Users should upgrade to the next release of free5GC that includes this commit. **Workarounds** There is no direct workaround at the application level. The recommendation is to apply the provided patch or restrict access to the NRF API to trusted sources only.