diff --git a/.changes/0b4c83e2-93d6-47f1-bcf3-83233e4438b2.json b/.changes/0b4c83e2-93d6-47f1-bcf3-83233e4438b2.json
new file mode 100644
index 00000000000..861cf9c92de
--- /dev/null
+++ b/.changes/0b4c83e2-93d6-47f1-bcf3-83233e4438b2.json
@@ -0,0 +1,6 @@
+{
+    "id": "0b4c83e2-93d6-47f1-bcf3-83233e4438b2",
+    "type": "bugfix",
+    "description": "Reject carriage return and line feed characters in ECS container authorization tokens",
+    "module": "aws-config"
+}
diff --git a/aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProvider.kt b/aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProvider.kt
index 116e553330f..9e598fe8bac 100644
--- a/aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProvider.kt
+++ b/aws-runtime/aws-config/common/src/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProvider.kt
@@ -116,7 +116,7 @@ public class EcsCredentialsProvider(
             ?: AwsSdkSetting.AwsContainerAuthorizationToken.resolve(platformProvider)
             ?: return null
 
-        if (token.contains("\r\n")) {
+        if (token.contains('\r') || token.contains('\n')) {
             throw CredentialsProviderException("Token contains illegal line break sequence.")
         }
 
diff --git a/aws-runtime/aws-config/common/test/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProviderTest.kt b/aws-runtime/aws-config/common/test/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProviderTest.kt
index 6d1ba64f044..52a5f28353c 100644
--- a/aws-runtime/aws-config/common/test/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProviderTest.kt
+++ b/aws-runtime/aws-config/common/test/aws/sdk/kotlin/runtime/auth/credentials/EcsCredentialsProviderTest.kt
@@ -386,7 +386,7 @@ class EcsCredentialsProviderTest {
 
     @Test
     fun testAuthTokenIllegal() = runTest {
-        val token = "auth\r\ntoken"
+    listOf("auth\rtoken", "auth\ntoken", "auth\r\ntoken").forEach { token ->
         val engine = TestConnection()
 
         val testPlatform = TestPlatformProvider.of(
@@ -400,12 +400,13 @@ class EcsCredentialsProviderTest {
         assertFailsWith<CredentialsProviderException> {
             provider.resolve()
         }.message.shouldContain("Token contains illegal line break sequence.")
+      }
     }
 
     @Test
     fun testAuthTokenFileIllegal() = runTest {
+    listOf("auth\rtoken", "auth\ntoken", "auth\r\ntoken").forEach { token ->
         val tokenFile = "/path/to/token"
-        val token = "auth\r\ntoken"
         val engine = TestConnection()
 
         val testPlatform = TestPlatformProvider.of(
@@ -422,6 +423,7 @@ class EcsCredentialsProviderTest {
         assertFailsWith<CredentialsProviderException> {
             provider.resolve()
         }.message.shouldContain("Token contains illegal line break sequence.")
+      }
     }
 
     @Test