void ExtensionService::OnExternalProviderReady() {
  CHECK(BrowserThread::CurrentlyOn(BrowserThread::UI));

  ProviderCollection::const_iterator i;
  for (i = external_extension_providers_.begin();
       i != external_extension_providers_.end(); ++i) {
    ExternalExtensionProviderInterface* provider = i->get();
    if (!provider->IsReady())
      return;
  }

  if (external_extension_url_added_ && updater()) {
    external_extension_url_added_ = false;
    updater()->CheckNow();
  }

  scoped_ptr<ExtensionPrefs::ExtensionsInfo> extensions_info(
      extension_prefs_->GetInstalledExtensionsInfo());
  for (size_t i = 0; i < extensions_info->size(); ++i) {
    ExtensionInfo* info = extensions_info->at(i).get();
    if (Extension::IsExternalLocation(info->extension_location))
      CheckExternalUninstall(info->extension_id);
  }
}

This category addresses vulnerabilities caused by flawed access control mechanisms, where incorrect permission settings allow unauthorized users to access restricted resources.