diff --git a/.changes/next-release/bugfix-24d6621e-32d3-45c5-a996-66232724e425.json b/.changes/next-release/bugfix-24d6621e-32d3-45c5-a996-66232724e425.json
new file mode 100644
index 0000000000..4bd408ec09
--- /dev/null
+++ b/.changes/next-release/bugfix-24d6621e-32d3-45c5-a996-66232724e425.json
@@ -0,0 +1,4 @@
+{
+  "type" : "bugfix",
+  "description" : "Amazon Q: Prevent IndexOutOfBoundsException by adding boundary checks for invalid range markers (#5187)"
+}
diff --git a/plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/telemetry/CodeWhispererUserModificationTracker.kt b/plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/telemetry/CodeWhispererUserModificationTracker.kt
index 80fa6c769a..b5ce5048c4 100644
--- a/plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/telemetry/CodeWhispererUserModificationTracker.kt
+++ b/plugins/amazonq/codewhisperer/jetbrains-community/src/software/aws/toolkits/jetbrains/services/codewhisperer/telemetry/CodeWhispererUserModificationTracker.kt
@@ -19,6 +19,7 @@ import org.assertj.core.util.VisibleForTesting
 import software.amazon.awssdk.services.codewhispererruntime.model.CodeWhispererRuntimeException
 import software.aws.toolkits.core.utils.debug
 import software.aws.toolkits.core.utils.getLogger
+import software.aws.toolkits.core.utils.warn
 import software.aws.toolkits.jetbrains.core.credentials.ToolkitConnection
 import software.aws.toolkits.jetbrains.services.codewhisperer.credentials.CodeWhispererClientAdaptor
 import software.aws.toolkits.jetbrains.services.codewhisperer.customization.CodeWhispererModelConfigurator
@@ -154,7 +155,7 @@ class CodeWhispererUserModificationTracker(private val project: Project) : Dispo
     private fun emitTelemetryOnSuggestion(acceptedSuggestion: AcceptedSuggestionEntry) {
         val file = acceptedSuggestion.vFile
 
-        if (file == null || (!file.isValid)) {
+        if (file == null || (!file.isValid) || !acceptedSuggestion.range.isValid) {
             sendModificationTelemetry(acceptedSuggestion, null)
             sendUserModificationTelemetryToServiceAPI(acceptedSuggestion)
         } else {
@@ -162,6 +163,20 @@ class CodeWhispererUserModificationTracker(private val project: Project) : Dispo
             val document = runReadAction {
                 FileDocumentManager.getInstance().getDocument(file)
             }
+            val start = acceptedSuggestion.range.startOffset
+            val end = acceptedSuggestion.range.endOffset
+            if (document != null) {
+                if (start < 0 || end < start || end > document.textLength) {
+                    LOG.warn {
+                        "Invalid range for suggestion ${acceptedSuggestion.requestId}: " +
+                            "start=$start, end=$end, docLength=${document.textLength}"
+                    }
+                    sendModificationTelemetry(acceptedSuggestion, null)
+                    sendUserModificationTelemetryToServiceAPI(acceptedSuggestion)
+                    return
+                }
+            }
+
             val currentString = document?.getText(
                 TextRange(acceptedSuggestion.range.startOffset, acceptedSuggestion.range.endOffset)
             )