diff --git a/pkg/logs/tailers/socket/tailer.go b/pkg/logs/tailers/socket/tailer.go
index ad28d251058d1..459f92a2fc15d 100644
--- a/pkg/logs/tailers/socket/tailer.go
+++ b/pkg/logs/tailers/socket/tailer.go
@@ -98,8 +98,7 @@ func (t *Tailer) readForever() {
 				log.Warnf("Couldn't read message from connection: %v", err)
 				return
 			}
-			copiedTags := make([]string, len(t.source.Config.Tags))
-			copy(copiedTags, t.source.Config.Tags)
+			msg := decoder.NewInput(data)
 			if ipAddress != "" && pkgconfigsetup.Datadog().GetBool("logs_config.use_sourcehost_tag") {
 				lastColonIndex := strings.LastIndex(ipAddress, ":")
 				var ipAddressWithoutPort string
@@ -109,10 +108,8 @@ func (t *Tailer) readForever() {
 					ipAddressWithoutPort = ipAddress
 				}
 				sourceHostTag := fmt.Sprintf("source_host:%s", ipAddressWithoutPort)
-				copiedTags = append(copiedTags, sourceHostTag)
+				msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, sourceHostTag)
 			}
-			msg := decoder.NewInput(data)
-			msg.ParsingExtra.Tags = append(msg.ParsingExtra.Tags, copiedTags...)
 			t.decoder.InputChan <- msg
 		}
 	}
diff --git a/pkg/logs/tailers/socket/tailer_test.go b/pkg/logs/tailers/socket/tailer_test.go
index 10a168b9788e8..128896663ce14 100644
--- a/pkg/logs/tailers/socket/tailer_test.go
+++ b/pkg/logs/tailers/socket/tailer_test.go
@@ -13,6 +13,7 @@ import (
 	"github.com/stretchr/testify/assert"
 
 	"github.com/DataDog/datadog-agent/comp/logs/agent/config"
+	pkgconfigsetup "github.com/DataDog/datadog-agent/pkg/config/setup"
 	"github.com/DataDog/datadog-agent/pkg/logs/message"
 	"github.com/DataDog/datadog-agent/pkg/logs/sources"
 )
@@ -58,6 +59,49 @@ func TestReadShouldFailWithError(t *testing.T) {
 	tailer.Stop()
 }
 
+func TestSourceHostTag(t *testing.T) {
+	msgChan := make(chan *message.Message)
+	r, w := net.Pipe()
+	logsConfig := &config.LogsConfig{
+		Tags: []string{"test:tag"},
+	}
+
+	logSource := sources.NewLogSource("test-source", logsConfig)
+	tailer := NewTailer(logSource, r, msgChan, readWithIP)
+	tailer.Start()
+
+	var msg *message.Message
+	w.Write([]byte("foo\n"))
+	msg = <-msgChan
+	assert.Equal(t, []string{"source_host:192.168.1.100", "test:tag"}, msg.Tags())
+	tailer.Stop()
+}
+
+func TestSourceHostTagFlagDisabled(t *testing.T) {
+	// Set the config flag for source_host tag to false
+	pkgconfigsetup.Datadog().BindEnvAndSetDefault("logs_config.use_sourcehost_tag", false)
+
+	// Set up test components
+	msgChan := make(chan *message.Message)
+	r, w := net.Pipe()
+	logsConfig := &config.LogsConfig{
+		Tags: []string{"test:tag"},
+	}
+
+	logSource := sources.NewLogSource("test-source", logsConfig)
+	tailer := NewTailer(logSource, r, msgChan, readWithIP)
+	tailer.Start()
+
+	var msg *message.Message
+	w.Write([]byte("foo\n"))
+	msg = <-msgChan
+
+	// Assert that only the original tag is present (source_host tag should not be added)
+	assert.Equal(t, []string{"test:tag"}, msg.Tags(), "source_host tag should not be added when flag is disabled")
+
+	tailer.Stop()
+}
+
 func read(tailer *Tailer) ([]byte, string, error) {
 	inBuf := make([]byte, 4096)
 	n, err := tailer.Conn.Read(inBuf)
@@ -66,3 +110,13 @@ func read(tailer *Tailer) ([]byte, string, error) {
 	}
 	return inBuf[:n], "", nil
 }
+
+func readWithIP(tailer *Tailer) ([]byte, string, error) {
+	inBuf := make([]byte, 4096)
+	n, err := tailer.Conn.Read(inBuf)
+	if err != nil {
+		return nil, "", err
+	}
+	mockIPAddress := "192.168.1.100:8080"
+	return inBuf[:n], mockIPAddress, nil
+}
diff --git a/releasenotes/notes/fix-duplicate-tags-e97e8eeb6492235f.yaml b/releasenotes/notes/fix-duplicate-tags-e97e8eeb6492235f.yaml
new file mode 100644
index 0000000000000..8612a09bd2115
--- /dev/null
+++ b/releasenotes/notes/fix-duplicate-tags-e97e8eeb6492235f.yaml
@@ -0,0 +1,12 @@
+# Each section from every release note are combined when the
+# CHANGELOG.rst is rendered. So the text needs to be worded so that
+# it does not depend on any information only available in another
+# section. This may mean repeating some details, but each section
+# must be readable independently of the other.
+#
+# Each section note must be formatted as reStructuredText.
+---
+fixes:
+  - |
+    Fix duplicate tags in UDP/TCP logs.
+
diff --git a/test/new-e2e/tests/agent-metrics-logs/log-agent/utils/file_tailing_utils.go b/test/new-e2e/tests/agent-metrics-logs/log-agent/utils/file_tailing_utils.go
index 7f9ab472bb80f..63e8398c33541 100644
--- a/test/new-e2e/tests/agent-metrics-logs/log-agent/utils/file_tailing_utils.go
+++ b/test/new-e2e/tests/agent-metrics-logs/log-agent/utils/file_tailing_utils.go
@@ -155,7 +155,7 @@ func FetchAndFilterLogs(fakeIntake *components.FakeIntake, service, content stri
 	return logs, nil
 }
 
-// CheckLogsExpected verifies the presence of expected logs.
+// CheckLogsExpected verifies the presence of expected logs, and verifies that there are no duplicate tags.
 func CheckLogsExpected(t *testing.T, fakeIntake *components.FakeIntake, service, content string, expectedTags ddtags) {
 	t.Helper()
 
@@ -167,6 +167,14 @@ func CheckLogsExpected(t *testing.T, fakeIntake *components.FakeIntake, service,
 			if assert.NotEmpty(c, logs, "Expected logs with content: '%s' not found. Instead, found: %s", content, intakeLog) {
 				t.Logf("Logs from service: '%s' with content: '%s' collected", service, content)
 				log := logs[0]
+				// Use a map to check for duplicate tags
+				seenTags := make(map[string]struct{})
+				for _, tag := range log.Tags {
+					if _, exists := seenTags[tag]; exists {
+						t.Errorf("Duplicate tag found: %s", tag)
+					}
+					seenTags[tag] = struct{}{} // Mark the tag as seen
+				}
 				for _, expectedTag := range expectedTags {
 					assert.Contains(t, log.Tags, expectedTag)
 				}