diff --git a/server/channels/api4/custom_profile_attributes.go b/server/channels/api4/custom_profile_attributes.go
index 2a992f7e25..277680fe4c 100644
--- a/server/channels/api4/custom_profile_attributes.go
+++ b/server/channels/api4/custom_profile_attributes.go
@@ -226,7 +226,7 @@ func patchCPAValues(c *Context, w http.ResponseWriter, r *http.Request) {
 
 	results := make(map[string]json.RawMessage, len(updates))
 	for fieldID, rawValue := range updates {
-		patchedValue, appErr := c.App.PatchCPAValue(userID, fieldID, rawValue)
+		patchedValue, appErr := c.App.PatchCPAValue(userID, fieldID, rawValue, false)
 		if appErr != nil {
 			c.Err = appErr
 			return
diff --git a/server/channels/api4/custom_profile_attributes_test.go b/server/channels/api4/custom_profile_attributes_test.go
index aded2c282c..a8936663ee 100644
--- a/server/channels/api4/custom_profile_attributes_test.go
+++ b/server/channels/api4/custom_profile_attributes_test.go
@@ -373,7 +373,7 @@ func TestListCPAValues(t *testing.T) {
 	require.Nil(t, appErr)
 	require.NotNil(t, createdField)
 
-	_, appErr = th.App.PatchCPAValue(th.BasicUser.Id, createdField.ID, json.RawMessage(`"Field Value"`))
+	_, appErr = th.App.PatchCPAValue(th.BasicUser.Id, createdField.ID, json.RawMessage(`"Field Value"`), true)
 	require.Nil(t, appErr)
 
 	t.Run("endpoint should not work if no valid license is present", func(t *testing.T) {
@@ -417,7 +417,7 @@ func TestListCPAValues(t *testing.T) {
 		require.Nil(t, appErr)
 		require.NotNil(t, createdArrayField)
 
-		_, appErr = th.App.PatchCPAValue(th.BasicUser.Id, createdArrayField.ID, json.RawMessage(fmt.Sprintf(`["%s", "%s"]`, optionID1, optionID2)))
+		_, appErr = th.App.PatchCPAValue(th.BasicUser.Id, createdArrayField.ID, json.RawMessage(fmt.Sprintf(`["%s", "%s"]`, optionID1, optionID2)), true)
 		require.Nil(t, appErr)
 
 		values, resp, err := th.Client.ListCPAValues(context.Background(), th.BasicUser.Id)
@@ -583,6 +583,64 @@ func TestPatchCPAValues(t *testing.T) {
 		require.Equal(t, optionsID[2:4], actualValues)
 	})
 
+	t.Run("should fail if any of the values belongs to a field that is LDAP/SAML synced", func(t *testing.T) {
+		// Create a field with LDAP attribute
+		ldapField, err := model.NewCPAFieldFromPropertyField(&model.PropertyField{
+			Name: model.NewId(),
+			Type: model.PropertyFieldTypeText,
+			Attrs: model.StringInterface{
+				model.CustomProfileAttributesPropertyAttrsLDAP: "ldap_attr",
+			},
+		})
+		require.NoError(t, err)
+
+		createdLDAPField, appErr := th.App.CreateCPAField(ldapField)
+		require.Nil(t, appErr)
+		require.NotNil(t, createdLDAPField)
+
+		// Create a field with SAML attribute
+		samlField, err := model.NewCPAFieldFromPropertyField(&model.PropertyField{
+			Name: model.NewId(),
+			Type: model.PropertyFieldTypeText,
+			Attrs: model.StringInterface{
+				model.CustomProfileAttributesPropertyAttrsSAML: "saml_attr",
+			},
+		})
+		require.NoError(t, err)
+
+		createdSAMLField, appErr := th.App.CreateCPAField(samlField)
+		require.Nil(t, appErr)
+		require.NotNil(t, createdSAMLField)
+
+		// Test LDAP field
+		values := map[string]json.RawMessage{
+			createdLDAPField.ID: json.RawMessage(`"LDAP Value"`),
+		}
+		_, resp, err := th.Client.PatchCPAValues(context.Background(), values)
+		CheckBadRequestStatus(t, resp)
+		require.Error(t, err)
+		CheckErrorID(t, err, "app.custom_profile_attributes.property_field_is_synced.app_error")
+
+		// Test SAML field
+		values = map[string]json.RawMessage{
+			createdSAMLField.ID: json.RawMessage(`"SAML Value"`),
+		}
+		_, resp, err = th.Client.PatchCPAValues(context.Background(), values)
+		CheckBadRequestStatus(t, resp)
+		require.Error(t, err)
+		CheckErrorID(t, err, "app.custom_profile_attributes.property_field_is_synced.app_error")
+
+		// Test multiple fields with one being LDAP synced
+		values = map[string]json.RawMessage{
+			createdField.ID:     json.RawMessage(`"Regular Value"`),
+			createdLDAPField.ID: json.RawMessage(`"LDAP Value"`),
+		}
+		_, resp, err = th.Client.PatchCPAValues(context.Background(), values)
+		CheckBadRequestStatus(t, resp)
+		require.Error(t, err)
+		CheckErrorID(t, err, "app.custom_profile_attributes.property_field_is_synced.app_error")
+	})
+
 	t.Run("an invalid patch should be rejected", func(t *testing.T) {
 		field, err := model.NewCPAFieldFromPropertyField(&model.PropertyField{
 			Name: model.NewId(),
diff --git a/server/channels/app/custom_profile_attributes.go b/server/channels/app/custom_profile_attributes.go
index 535d469207..194ef82629 100644
--- a/server/channels/app/custom_profile_attributes.go
+++ b/server/channels/app/custom_profile_attributes.go
@@ -210,8 +210,8 @@ func (a *App) GetCPAValue(valueID string) (*model.PropertyValue, *model.AppError
 	return value, nil
 }
 
-func (a *App) PatchCPAValue(userID string, fieldID string, value json.RawMessage) (*model.PropertyValue, *model.AppError) {
-	values, appErr := a.PatchCPAValues(userID, map[string]json.RawMessage{fieldID: value})
+func (a *App) PatchCPAValue(userID string, fieldID string, value json.RawMessage, allowSynced bool) (*model.PropertyValue, *model.AppError) {
+	values, appErr := a.PatchCPAValues(userID, map[string]json.RawMessage{fieldID: value}, allowSynced)
 	if appErr != nil {
 		return nil, appErr
 	}
@@ -219,7 +219,7 @@ func (a *App) PatchCPAValue(userID string, fieldID string, value json.RawMessage
 	return values[0], nil
 }
 
-func (a *App) PatchCPAValues(userID string, fieldValueMap map[string]json.RawMessage) ([]*model.PropertyValue, *model.AppError) {
+func (a *App) PatchCPAValues(userID string, fieldValueMap map[string]json.RawMessage, allowSynced bool) ([]*model.PropertyValue, *model.AppError) {
 	groupID, err := a.CpaGroupID()
 	if err != nil {
 		return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.cpa_group_id.app_error", nil, "", http.StatusInternalServerError).Wrap(err)
@@ -230,19 +230,23 @@ func (a *App) PatchCPAValues(userID string, fieldValueMap map[string]json.RawMes
 		// make sure field exists in this group
 		existingField, appErr := a.GetCPAField(fieldID)
 		if appErr != nil {
-			return nil, model.NewAppError("PatchCPAValue", "app.custom_profile_attributes.property_field_not_found.app_error", nil, "", http.StatusNotFound).Wrap(appErr)
+			return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.property_field_not_found.app_error", nil, "", http.StatusNotFound).Wrap(appErr)
 		} else if existingField.DeleteAt > 0 {
-			return nil, model.NewAppError("PatchCPAValue", "app.custom_profile_attributes.property_field_not_found.app_error", nil, "", http.StatusNotFound)
+			return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.property_field_not_found.app_error", nil, "", http.StatusNotFound)
 		}
 
 		cpaField, fErr := model.NewCPAFieldFromPropertyField(existingField)
 		if fErr != nil {
-			return nil, model.NewAppError("PatchCPAValue", "app.custom_profile_attributes.property_field_conversion.app_error", nil, "", http.StatusInternalServerError).Wrap(fErr)
+			return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.property_field_conversion.app_error", nil, "", http.StatusInternalServerError).Wrap(fErr)
+		}
+
+		if !allowSynced && cpaField.IsSynced() {
+			return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.property_field_is_synced.app_error", nil, "", http.StatusBadRequest)
 		}
 
 		sanitizedValue, sErr := model.SanitizeAndValidatePropertyValue(cpaField, rawValue)
 		if sErr != nil {
-			return nil, model.NewAppError("PatchCPAValue", "app.custom_profile_attributes.validate_value.app_error", nil, "", http.StatusBadRequest).Wrap(sErr)
+			return nil, model.NewAppError("PatchCPAValues", "app.custom_profile_attributes.validate_value.app_error", nil, "", http.StatusBadRequest).Wrap(sErr)
 		}
 
 		value := &model.PropertyValue{
diff --git a/server/channels/app/custom_profile_attributes_test.go b/server/channels/app/custom_profile_attributes_test.go
index b930da271d..0f25bdf283 100644
--- a/server/channels/app/custom_profile_attributes_test.go
+++ b/server/channels/app/custom_profile_attributes_test.go
@@ -65,6 +65,60 @@ func TestGetCPAField(t *testing.T) {
 		require.Equal(t, "Test Field", fetchedField.Name)
 		require.Equal(t, model.CustomProfileAttributesVisibilityHidden, fetchedField.Attrs["visibility"])
 	})
+
+	t.Run("should validate LDAP/SAML synced fields", func(t *testing.T) {
+		// Create LDAP synced field
+		ldapField, err := model.NewCPAFieldFromPropertyField(&model.PropertyField{
+			GroupID: cpaGroupID,
+			Name:    "LDAP Field",
+			Type:    model.PropertyFieldTypeText,
+			Attrs: model.StringInterface{
+				model.CustomProfileAttributesPropertyAttrsLDAP: "ldap_attribute",
+			},
+		})
+		require.NoError(t, err)
+		createdLDAPField, appErr := th.App.CreateCPAField(ldapField)
+		require.Nil(t, appErr)
+
+		// Create SAML synced field
+		samlField, err := model.NewCPAFieldFromPropertyField(&model.PropertyField{
+			GroupID: cpaGroupID,
+			Name:    "SAML Field",
+			Type:    model.PropertyFieldTypeText,
+			Attrs: model.StringInterface{
+				model.CustomProfileAttributesPropertyAttrsSAML: "saml_attribute",
+			},
+		})
+		require.NoError(t, err)
+		createdSAMLField, appErr := th.App.CreateCPAField(samlField)
+		require.Nil(t, appErr)
+
+		// Test with allowSynced=false
+		userID := model.NewId()
+
+		// Test LDAP field
+		_, appErr = th.App.PatchCPAValue(userID, createdLDAPField.ID, json.RawMessage(`"test value"`), false)
+		require.NotNil(t, appErr)
+		require.Equal(t, "app.custom_profile_attributes.property_field_is_synced.app_error", appErr.Id)
+
+		// Test SAML field
+		_, appErr = th.App.PatchCPAValue(userID, createdSAMLField.ID, json.RawMessage(`"test value"`), false)
+		require.NotNil(t, appErr)
+		require.Equal(t, "app.custom_profile_attributes.property_field_is_synced.app_error", appErr.Id)
+
+		// Test with allowSynced=true
+		// LDAP field should work
+		patchedValue, appErr := th.App.PatchCPAValue(userID, createdLDAPField.ID, json.RawMessage(`"test value"`), true)
+		require.Nil(t, appErr)
+		require.NotNil(t, patchedValue)
+		require.Equal(t, json.RawMessage(`"test value"`), patchedValue.Value)
+
+		// SAML field should work
+		patchedValue, appErr = th.App.PatchCPAValue(userID, createdSAMLField.ID, json.RawMessage(`"test value"`), true)
+		require.Nil(t, appErr)
+		require.NotNil(t, patchedValue)
+		require.Equal(t, json.RawMessage(`"test value"`), patchedValue.Value)
+	})
 }
 
 func TestListCPAFields(t *testing.T) {
@@ -584,7 +638,7 @@ func TestPatchCPAValue(t *testing.T) {
 
 	t.Run("should fail if the field doesn't exist", func(t *testing.T) {
 		invalidFieldID := model.NewId()
-		_, appErr := th.App.PatchCPAValue(model.NewId(), invalidFieldID, json.RawMessage(`"fieldValue"`))
+		_, appErr := th.App.PatchCPAValue(model.NewId(), invalidFieldID, json.RawMessage(`"fieldValue"`), true)
 		require.NotNil(t, appErr)
 	})
 
@@ -598,14 +652,14 @@ func TestPatchCPAValue(t *testing.T) {
 		require.NoError(t, err)
 
 		userID := model.NewId()
-		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"test value"`))
+		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"test value"`), true)
 		require.Nil(t, appErr)
 		require.NotNil(t, patchedValue)
 		require.Equal(t, json.RawMessage(`"test value"`), patchedValue.Value)
 		require.Equal(t, userID, patchedValue.TargetID)
 
 		t.Run("should correctly patch the CPA property value", func(t *testing.T) {
-			patch2, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"new patched value"`))
+			patch2, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"new patched value"`), true)
 			require.Nil(t, appErr)
 			require.NotNil(t, patch2)
 			require.Equal(t, patchedValue.ID, patch2.ID)
@@ -626,7 +680,7 @@ func TestPatchCPAValue(t *testing.T) {
 		require.NoError(t, err)
 
 		userID := model.NewId()
-		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"test value"`))
+		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(`"test value"`), true)
 		require.NotNil(t, appErr)
 		require.Nil(t, patchedValue)
 	})
@@ -653,7 +707,7 @@ func TestPatchCPAValue(t *testing.T) {
 		optionJSON := fmt.Sprintf(`["%s", "%s", "%s"]`, optionsID[0], optionsID[1], optionsID[2])
 
 		userID := model.NewId()
-		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(optionJSON))
+		patchedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(optionJSON), true)
 		require.Nil(t, appErr)
 		require.NotNil(t, patchedValue)
 		var arrayValues []string
@@ -663,7 +717,7 @@ func TestPatchCPAValue(t *testing.T) {
 
 		// Update array values with valid option IDs
 		updatedOptionJSON := fmt.Sprintf(`["%s", "%s"]`, optionsID[1], optionsID[3])
-		updatedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(updatedOptionJSON))
+		updatedValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(updatedOptionJSON), true)
 		require.Nil(t, appErr)
 		require.NotNil(t, updatedValue)
 		require.Equal(t, patchedValue.ID, updatedValue.ID)
@@ -677,21 +731,21 @@ func TestPatchCPAValue(t *testing.T) {
 			invalidID := model.NewId()
 			invalidOptionJSON := fmt.Sprintf(`["%s", "%s"]`, optionsID[0], invalidID)
 
-			invalidValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(invalidOptionJSON))
+			invalidValue, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(invalidOptionJSON), true)
 			require.NotNil(t, appErr)
 			require.Nil(t, invalidValue)
 			require.Equal(t, "app.custom_profile_attributes.validate_value.app_error", appErr.Id)
 
 			// Test with completely invalid JSON format
 			invalidJSON := `[not valid json]`
-			invalidValue, appErr = th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(invalidJSON))
+			invalidValue, appErr = th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(invalidJSON), true)
 			require.NotNil(t, appErr)
 			require.Nil(t, invalidValue)
 			require.Equal(t, "app.custom_profile_attributes.validate_value.app_error", appErr.Id)
 
 			// Test with wrong data type (sending string instead of array)
 			wrongTypeJSON := `"not an array"`
-			invalidValue, appErr = th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(wrongTypeJSON))
+			invalidValue, appErr = th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(wrongTypeJSON), true)
 			require.NotNil(t, appErr)
 			require.Nil(t, invalidValue)
 			require.Equal(t, "app.custom_profile_attributes.validate_value.app_error", appErr.Id)
@@ -725,7 +779,7 @@ func TestDeleteCPAValues(t *testing.T) {
 		createdFields = append(createdFields, createdField)
 
 		// Create a value for this field
-		value, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(fmt.Sprintf(`"Value %d"`, i)))
+		value, appErr := th.App.PatchCPAValue(userID, createdField.ID, json.RawMessage(fmt.Sprintf(`"Value %d"`, i)), false)
 		require.Nil(t, appErr)
 		require.NotNil(t, value)
 	}
@@ -754,7 +808,7 @@ func TestDeleteCPAValues(t *testing.T) {
 	t.Run("should not affect values for other users", func(t *testing.T) {
 		// Create values for another user
 		for _, field := range createdFields {
-			value, appErr := th.App.PatchCPAValue(otherUserID, field.ID, json.RawMessage(`"Other user value"`))
+			value, appErr := th.App.PatchCPAValue(otherUserID, field.ID, json.RawMessage(`"Other user value"`), false)
 			require.Nil(t, appErr)
 			require.NotNil(t, value)
 		}
diff --git a/server/i18n/en.json b/server/i18n/en.json
index 8278441906..81d736699f 100644
--- a/server/i18n/en.json
+++ b/server/i18n/en.json
@@ -5078,6 +5078,10 @@
     "id": "app.custom_profile_attributes.property_field_delete.app_error",
     "translation": "Unable to delete Custom Profile Attribute field"
   },
+  {
+    "id": "app.custom_profile_attributes.property_field_is_synced.app_error",
+    "translation": "Cannot update value for a synced Custom Profile Attribute field"
+  },
   {
     "id": "app.custom_profile_attributes.property_field_not_found.app_error",
     "translation": "Custom Profile Attribute field not found"
diff --git a/server/public/model/custom_profile_attributes.go b/server/public/model/custom_profile_attributes.go
index 1beecf28c0..a837234351 100644
--- a/server/public/model/custom_profile_attributes.go
+++ b/server/public/model/custom_profile_attributes.go
@@ -133,6 +133,10 @@ type CPAAttrs struct {
 	SAML       string                                                `json:"saml"`
 }
 
+func (c *CPAField) IsSynced() bool {
+	return c.Attrs.LDAP != "" || c.Attrs.SAML != ""
+}
+
 func (c *CPAField) ToPropertyField() *PropertyField {
 	pf := c.PropertyField
 
@@ -234,7 +238,8 @@ func NewCPAFieldFromPropertyField(pf *PropertyField) (*CPAField, error) {
 	}, nil
 }
 
-// SanitizeAndValidatePropertyValue validates and sanitizes the given property value based on the field type
+// SanitizeAndValidatePropertyValue validates and sanitizes the given
+// property value based on the field type
 func SanitizeAndValidatePropertyValue(cpaField *CPAField, rawValue json.RawMessage) (json.RawMessage, error) {
 	fieldType := cpaField.Type