MobSF is a mobile application security testing tool used. Prior to 4.5.1, get_browsable_activities in mobsf/StaticAnalyzer/views/android/manifest_analysis.py validates only an Android manifest android:host value with valid_host before appending a separately supplied android:port to the URL fetched by _check_url, allowing an authenticated user to upload a crafted APK that makes requests to an attacker-selected nonstandard port at /.well-known/assetlinks.json. With an attacker-controlled hostname and DNS rebinding between validation and the requests.get connection, the request can reach an internal service, although redirects remain disabled and the path is fixed. This issue is fixed in version 4.5.1.