diff --git a/management/internals/modules/reverseproxy/service/service.go b/management/internals/modules/reverseproxy/service/service.go
index 769e037bc..166a66a5f 100644
--- a/management/internals/modules/reverseproxy/service/service.go
+++ b/management/internals/modules/reverseproxy/service/service.go
@@ -381,13 +381,14 @@ func (s *Service) buildPathMappings() []*proto.PathMapping {
 		}
 
 		// HTTP/HTTPS: build full URL
+		hostNoBrackets := strings.TrimSuffix(strings.TrimPrefix(target.Host, "["), "]")
 		targetURL := url.URL{
 			Scheme: target.Protocol,
-			Host:   target.Host,
+			Host:   bracketIPv6Host(hostNoBrackets),
 			Path:   "/",
 		}
 		if target.Port > 0 && !isDefaultPort(target.Protocol, target.Port) {
-			targetURL.Host = net.JoinHostPort(targetURL.Host, strconv.FormatUint(uint64(target.Port), 10))
+			targetURL.Host = net.JoinHostPort(hostNoBrackets, strconv.FormatUint(uint64(target.Port), 10))
 		}
 
 		path := "/"
@@ -405,6 +406,19 @@ func (s *Service) buildPathMappings() []*proto.PathMapping {
 	return pathMappings
 }
 
+// bracketIPv6Host wraps host in square brackets when it is an IPv6 literal, as
+// required for the Host field of net/url.URL (RFC 3986 §3.2.2). v4-mapped IPv6
+// addresses are bracketed too since their textual form contains colons.
+func bracketIPv6Host(host string) string {
+	if strings.HasPrefix(host, "[") {
+		return host
+	}
+	if addr, err := netip.ParseAddr(host); err == nil && addr.Is6() {
+		return "[" + host + "]"
+	}
+	return host
+}
+
 func operationToProtoType(op Operation) proto.ProxyMappingUpdateType {
 	switch op {
 	case Create:
diff --git a/management/internals/modules/reverseproxy/service/service_test.go b/management/internals/modules/reverseproxy/service/service_test.go
index ff54cb79f..f1349ff65 100644
--- a/management/internals/modules/reverseproxy/service/service_test.go
+++ b/management/internals/modules/reverseproxy/service/service_test.go
@@ -351,6 +351,83 @@ func TestToProtoMapping_PortInTargetURL(t *testing.T) {
 			port:       80,
 			wantTarget: "https://10.0.0.1:80/",
 		},
+		{
+			name:       "domain host without port is unchanged",
+			protocol:   "http",
+			host:       "example.com",
+			port:       0,
+			wantTarget: "http://example.com/",
+		},
+		{
+			name:       "domain host with non-default port is unchanged",
+			protocol:   "http",
+			host:       "example.com",
+			port:       8080,
+			wantTarget: "http://example.com:8080/",
+		},
+		{
+			name:       "ipv6 host without port is bracketed",
+			protocol:   "http",
+			host:       "fb00:cafe:1::3",
+			port:       0,
+			wantTarget: "http://[fb00:cafe:1::3]/",
+		},
+		{
+			name:       "ipv6 host with default port omits port and brackets host",
+			protocol:   "http",
+			host:       "fb00:cafe:1::3",
+			port:       80,
+			wantTarget: "http://[fb00:cafe:1::3]/",
+		},
+		{
+			name:       "ipv6 host with non-default port is bracketed",
+			protocol:   "http",
+			host:       "fb00:cafe:1::3",
+			port:       8080,
+			wantTarget: "http://[fb00:cafe:1::3]:8080/",
+		},
+		{
+			name:       "ipv6 loopback without port is bracketed",
+			protocol:   "http",
+			host:       "::1",
+			port:       0,
+			wantTarget: "http://[::1]/",
+		},
+		{
+			name:       "ipv6 host with 5-digit port is bracketed",
+			protocol:   "http",
+			host:       "fb00:cafe::1",
+			port:       18080,
+			wantTarget: "http://[fb00:cafe::1]:18080/",
+		},
+		{
+			name:       "pre-bracketed ipv6 without port stays single-bracketed",
+			protocol:   "http",
+			host:       "[fb00:cafe::1]",
+			port:       0,
+			wantTarget: "http://[fb00:cafe::1]/",
+		},
+		{
+			name:       "pre-bracketed ipv6 with port is not double-bracketed",
+			protocol:   "http",
+			host:       "[fb00:cafe::1]",
+			port:       8080,
+			wantTarget: "http://[fb00:cafe::1]:8080/",
+		},
+		{
+			name:       "v4-mapped ipv6 host without port is bracketed",
+			protocol:   "http",
+			host:       "::ffff:10.0.0.1",
+			port:       0,
+			wantTarget: "http://[::ffff:10.0.0.1]/",
+		},
+		{
+			name:       "full-form 8-group ipv6 without port is bracketed",
+			protocol:   "http",
+			host:       "fb00:cafe:1:0:0:0:0:3",
+			port:       0,
+			wantTarget: "http://[fb00:cafe:1:0:0:0:0:3]/",
+		},
 	}
 	for _, tt := range tests {
 		t.Run(tt.name, func(t *testing.T) {