diff --git a/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytes.cs b/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytes.cs
index 5f56d4476d27d3..f5125531ec3aee 100644
--- a/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytes.cs
+++ b/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytes.cs
@@ -111,9 +111,11 @@ public void WriteToReadOnlyFile()
             {
                 if (PlatformDetection.IsNotWindows && PlatformDetection.IsPrivilegedProcess)
                 {
-                    File.WriteAllBytes(path, "text"u8.ToArray());
-                    File.WriteAllBytes(path, "text"u8);
-                    Assert.Equal("texttext"u8.ToArray(), File.ReadAllBytes(path));
+                    File.WriteAllBytes(path, "text1"u8.ToArray());
+                    Assert.Equal("text1"u8.ToArray(), File.ReadAllBytes(path));
+                    
+                    File.WriteAllBytes(path, "text2"u8);
+                    Assert.Equal("text2"u8.ToArray(), File.ReadAllBytes(path));
                 }
                 else
                 {
diff --git a/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytesAsync.cs b/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytesAsync.cs
index 662e4aa109100e..1a3be92809601c 100644
--- a/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytesAsync.cs
+++ b/src/libraries/System.Runtime/tests/System.IO.FileSystem.Tests/File/ReadWriteAllBytesAsync.cs
@@ -123,9 +123,11 @@ public async Task WriteToReadOnlyFileAsync()
             {
                 if (PlatformDetection.IsNotWindows && PlatformDetection.IsPrivilegedProcess)
                 {
-                    await File.WriteAllBytesAsync(path, "text"u8.ToArray());
-                    await File.WriteAllBytesAsync(path, "text"u8.ToArray().AsMemory());
-                    Assert.Equal("texttext"u8.ToArray(), await File.ReadAllBytesAsync(path));
+                    await File.WriteAllBytesAsync(path, "text1"u8.ToArray());
+                    Assert.Equal("text1"u8.ToArray(), await File.ReadAllBytesAsync(path));
+
+                    await File.WriteAllBytesAsync(path, "text2"u8.ToArray().AsMemory());
+                    Assert.Equal("text2"u8.ToArray(), await File.ReadAllBytesAsync(path));
                 }
                 else
                 {