--- a/src/netaddress.cpp
+++ b/src/netaddress.cpp
@@ -132,6 +132,7 @@ CNetAddr::CNetAddr(const struct in_addr& ipv4Addr)
 CNetAddr::CNetAddr(const struct in6_addr& ipv6Addr, const uint32_t scope)
 {
     SetLegacyIPv6(Span<const uint8_t>(reinterpret_cast<const uint8_t*>(&ipv6Addr), sizeof(ipv6Addr)));
+    assert(scope == 0);
     scopeId = scope;
 }
 
@@ -716,6 +717,7 @@ bool CService::GetSockAddr(struct sockaddr* paddr, socklen_t *addrlen) const
+        assert(scopeId == 0);
         paddrin6->sin6_scope_id = scopeId;
--- a/src/netbase.cpp
+++ b/src/netbase.cpp
@@ -120,6 +120,7 @@ bool static LookupIntern(const std::string& name, std::vector<CNetAddr>& vIP, un
             struct sockaddr_in6* s6 = (struct sockaddr_in6*) aiTrav->ai_addr;
+            assert(s6->sin6_scope_id == 0);
             resolved = CNetAddr(s6->sin6_addr, s6->sin6_scope_id);
         }