diff --git a/signer/core/api_test.go b/signer/core/api_test.go
index f7514f2bd6..4b92e149bc 100644
--- a/signer/core/api_test.go
+++ b/signer/core/api_test.go
@@ -41,9 +41,9 @@ import (
 
 // Used for testing
 type headlessUi struct {
-	approveCh    chan string // to send approve/deny
-	inputCh      chan string // to send password
-	infoMessages []string
+	approveCh                   chan string // to send approve/deny
+	inputCh                     chan string // to send password
+	infoMessages, errorMessages []string
 }
 
 func (ui *headlessUi) OnInputRequired(info core.UserInputRequest) (core.UserInputResponse, error) {
@@ -100,6 +100,7 @@ func (ui *headlessUi) ApproveNewAccount(request *core.NewAccountRequest) (core.N
 func (ui *headlessUi) ShowError(message string) {
 	//stdout is used by communication
 	fmt.Fprintln(os.Stderr, message)
+	ui.errorMessages = append(ui.errorMessages, message)
 }
 
 func (ui *headlessUi) ShowInfo(message string) {
@@ -122,7 +123,7 @@ func setup(t *testing.T, enableSIWE bool) (*core.SignerAPI, *headlessUi) {
 	if err != nil {
 		t.Fatal(err.Error())
 	}
-	ui := &headlessUi{make(chan string, 20), make(chan string, 20), []string{}}
+	ui := &headlessUi{make(chan string, 20), make(chan string, 20), []string{}, []string{}}
 	am := core.StartClefAccountManager(tmpDirName(t), true, true, "")
 	api := core.NewSignerAPI(am, 1337, true, ui, db, true, &storage.NoStorage{}, enableSIWE)
 	return api, ui
diff --git a/signer/core/signed_data_test.go b/signer/core/signed_data_test.go
index 85bfbc609d..9176714d6f 100644
--- a/signer/core/signed_data_test.go
+++ b/signer/core/signed_data_test.go
@@ -1088,6 +1088,8 @@ func TestSignInWithEtheriumValidLocalhost(t *testing.T) {
 			control.inputCh <- "a_long_password"
 			signature, err := api.SignData(ctx, apitypes.TextPlain.Mime, a, hexutil.Encode([]byte(message)))
 			require.NoError(t, err)
+			require.Equal(t, 0, len(control.infoMessages))
+			require.Equal(t, 0, len(control.errorMessages))
 
 			if signature == nil || len(signature) != 65 {
 				t.Errorf("Expected 65 byte signature (got %d bytes)", len(signature))
@@ -1120,7 +1122,8 @@ func TestSignInWithEtheriumValidMessages(t *testing.T) {
 			control.inputCh <- "a_long_password"
 			signature, err := api.SignData(ctx, apitypes.TextPlain.Mime, a, hexutil.Encode([]byte(message)))
 			require.NoError(t, err)
-			// todo: check UI for warning message
+			require.Equal(t, 0, len(control.infoMessages))
+			require.Equal(t, 0, len(control.errorMessages))
 
 			if signature == nil || len(signature) != 65 {
 				t.Errorf("Expected 65 byte signature (got %d bytes)", len(signature))
@@ -1138,6 +1141,7 @@ func TestSignInWithEtheriumInvlid(t *testing.T) {
 			Source    string `json:"source"`
 			Account   string `json:"account"`
 		} `json:"request_context"`
+		ErrorMsgPattern string `json:"error_msg_pattern"`
 	}
 	jsonFile, err := os.ReadFile(filepath.Join("testdata", "siwe", "error_spoofing.json"))
 	require.NoError(t, err)
@@ -1164,8 +1168,15 @@ func TestSignInWithEtheriumInvlid(t *testing.T) {
 				_, err = api.SignData(ctx, apitypes.TextPlain.Mime, a, hexutil.Encode([]byte(message)))
 				if enabled {
 					require.Error(t, err)
+
+					require.Equal(t, 0, len(control.infoMessages))
+					require.Equal(t, 1, len(control.errorMessages))
+					require.Regexp(t, testData.ErrorMsgPattern, err.Error())
 				} else {
 					require.NoError(t, err)
+
+					require.Equal(t, 0, len(control.infoMessages))
+					require.Equal(t, 0, len(control.errorMessages))
 				}
 			})
 		}
@@ -1198,6 +1209,7 @@ func TestSignInWithEtheriumWarning(t *testing.T) {
 			require.NoError(t, err)
 			require.Equal(t, 1, len(control.infoMessages))
 			require.Equal(t, core.ErrMalformedSIWEMessage.Error(), control.infoMessages[0])
+			require.Equal(t, 0, len(control.errorMessages))
 
 			if signature == nil || len(signature) != 65 {
 				t.Errorf("Expected 65 byte signature (got %d bytes)", len(signature))
diff --git a/signer/core/testdata/siwe/error_spoofing.json b/signer/core/testdata/siwe/error_spoofing.json
index 308703a6a2..563a0ddaf7 100644
--- a/signer/core/testdata/siwe/error_spoofing.json
+++ b/signer/core/testdata/siwe/error_spoofing.json
@@ -4,14 +4,16 @@
         "request_context": {
             "transport": "http",
             "source": "localhost:4361"
-        }
+        },
+        "error_msg_pattern": "sign in request domain \\(https://localhost:4361\\) does not match source: http://localhost:4361"
     },
     "spoofed_source": {
         "msg": "https://important-website.com wants you to sign in with your Ethereum account:\n{{Account}}\n\nSIWE Notepad Example\n\nURI: https://important-website.com\nVersion: 1\nChain ID: 1\nNonce: b19JyMHnM0Jdm20as\nIssued At: 2022-04-19T18:57:09.490Z",
         "request_context": {
             "transport": "https",
             "source": "bad-website.com"
-        }
+        },
+        "error_msg_pattern": "sign in request domain \\(https://important-website.com\\) does not match source: https://bad-website.com"
     },
     "spoofed_account": {
         "msg": "localhost:4361 wants you to sign in with your Ethereum account:\n{{Account}}\n\nSIWE Notepad Example\n\nURI: https://localhost:4361\nVersion: 1\nChain ID: 1\nNonce: b19JyMHnM0Jdm20as\nIssued At: 2022-04-19T18:57:09.490Z",
@@ -19,6 +21,7 @@
             "transport": "https",
             "source": "localhost:4361",
             "account": "0x1234567890123456789012345678901234567890"
-        }
+        },
+        "error_msg_pattern": "sign in request address \\(0x1234567890123456789012345678901234567890\\) does not match source: 0x.*"
     }
 }