diff --git a/src/Microsoft.AspNetCore.Server.Kestrel/Infrastructure/AsciiUtilities.cs b/src/Microsoft.AspNetCore.Server.Kestrel/Infrastructure/AsciiUtilities.cs
index 69d6fda2aa..2d9a04ee5b 100644
--- a/src/Microsoft.AspNetCore.Server.Kestrel/Infrastructure/AsciiUtilities.cs
+++ b/src/Microsoft.AspNetCore.Server.Kestrel/Infrastructure/AsciiUtilities.cs
@@ -8,73 +8,72 @@ namespace Microsoft.AspNetCore.Server.Kestrel.Infrastructure
         public static unsafe bool TryGetAsciiString(byte* input, char* output, int count)
         {
             var i = 0;
-            int orValue = 0;
-            bool hasZero = false;
+            sbyte* signedInput = (sbyte*)input;
+
+            bool isValid = true;
             while (i < count - 11)
             {
-                orValue |= *input | *(input + 1) | *(input + 2) | *(input + 3) | *(input + 4) | *(input + 5) |
-                    *(input + 6) | *(input + 7) | *(input + 8) | *(input + 9) | *(input + 10) | *(input + 11);
-                hasZero = hasZero || *input == 0 || *(input + 1) == 0 || *(input + 2) == 0 || *(input + 3) == 0 ||
-                    *(input + 4) == 0 || *(input + 5) == 0 || *(input + 6) == 0 || *(input + 7) == 0 ||
-                    *(input + 8) == 0 || *(input + 9) == 0 || *(input + 10) == 0 || *(input + 11) == 0;
+                isValid = isValid && *signedInput > 0 && *(signedInput + 1) > 0 && *(signedInput + 2) > 0 &&
+                    *(signedInput + 3) > 0 && *(signedInput + 4) > 0 && *(signedInput + 5) > 0 && *(signedInput + 6) > 0 &&
+                    *(signedInput + 7) > 0 && *(signedInput + 8) > 0 && *(signedInput + 9) > 0 && *(signedInput + 10) > 0 &&
+                    *(signedInput + 11) > 0;
 
                 i += 12;
-                *(output) = (char)*(input);
-                *(output + 1) = (char)*(input + 1);
-                *(output + 2) = (char)*(input + 2);
-                *(output + 3) = (char)*(input + 3);
-                *(output + 4) = (char)*(input + 4);
-                *(output + 5) = (char)*(input + 5);
-                *(output + 6) = (char)*(input + 6);
-                *(output + 7) = (char)*(input + 7);
-                *(output + 8) = (char)*(input + 8);
-                *(output + 9) = (char)*(input + 9);
-                *(output + 10) = (char)*(input + 10);
-                *(output + 11) = (char)*(input + 11);
+                *(output) = (char)*(signedInput);
+                *(output + 1) = (char)*(signedInput + 1);
+                *(output + 2) = (char)*(signedInput + 2);
+                *(output + 3) = (char)*(signedInput + 3);
+                *(output + 4) = (char)*(signedInput + 4);
+                *(output + 5) = (char)*(signedInput + 5);
+                *(output + 6) = (char)*(signedInput + 6);
+                *(output + 7) = (char)*(signedInput + 7);
+                *(output + 8) = (char)*(signedInput + 8);
+                *(output + 9) = (char)*(signedInput + 9);
+                *(output + 10) = (char)*(signedInput + 10);
+                *(output + 11) = (char)*(signedInput + 11);
                 output += 12;
-                input += 12;
+                signedInput += 12;
             }
             if (i < count - 5)
             {
-                orValue |= *input | *(input + 1) | *(input + 2) | *(input + 3) | *(input + 4) | *(input + 5);
-                hasZero = hasZero || *input == 0 || *(input + 1) == 0 || *(input + 2) == 0 || *(input + 3) == 0 ||
-                    *(input + 4) == 0 || *(input + 5) == 0;
+                isValid = isValid && *signedInput > 0 && *(signedInput + 1) > 0 && *(signedInput + 2) > 0 &&
+                    *(signedInput + 3) > 0 && *(signedInput + 4) > 0 && *(signedInput + 5) > 0;
 
                 i += 6;
-                *(output) = (char)*(input);
-                *(output + 1) = (char)*(input + 1);
-                *(output + 2) = (char)*(input + 2);
-                *(output + 3) = (char)*(input + 3);
-                *(output + 4) = (char)*(input + 4);
-                *(output + 5) = (char)*(input + 5);
+                *(output) = (char)*(signedInput);
+                *(output + 1) = (char)*(signedInput + 1);
+                *(output + 2) = (char)*(signedInput + 2);
+                *(output + 3) = (char)*(signedInput + 3);
+                *(output + 4) = (char)*(signedInput + 4);
+                *(output + 5) = (char)*(signedInput + 5);
                 output += 6;
-                input += 6;
+                signedInput += 6;
             }
             if (i < count - 3)
             {
-                orValue |= *input | *(input + 1) | *(input + 2) | *(input + 3);
-                hasZero = hasZero || *input == 0 || *(input + 1) == 0 || *(input + 2) == 0 || *(input + 3) == 0;
+                isValid = isValid && *signedInput > 0 && *(signedInput + 1) > 0 && *(signedInput + 2) > 0 &&
+                    *(signedInput + 3) > 0;
 
                 i += 4;
-                *(output) = (char)*(input);
-                *(output + 1) = (char)*(input + 1);
-                *(output + 2) = (char)*(input + 2);
-                *(output + 3) = (char)*(input + 3);
+                *(output) = (char)*(signedInput);
+                *(output + 1) = (char)*(signedInput + 1);
+                *(output + 2) = (char)*(signedInput + 2);
+                *(output + 3) = (char)*(signedInput + 3);
                 output += 4;
-                input += 4;
+                signedInput += 4;
             }
 
             while (i < count)
             {
-                orValue |= *input;
-                hasZero = hasZero || *input == 0;
+                isValid = isValid && *signedInput > 0;
+
                 i++;
-                *output = (char)*input;
+                *output = (char)*signedInput;
                 output++;
-                input++;
+                signedInput++;
             }
 
-            return (orValue & 0x80) == 0 && !hasZero;
+            return isValid;
         }
     }
 }