diff --git a/Sources/CryptorRSA/CryptorRSAUtilities.swift b/Sources/CryptorRSA/CryptorRSAUtilities.swift
index d2e8a82..ae47907 100644
--- a/Sources/CryptorRSA/CryptorRSAUtilities.swift
+++ b/Sources/CryptorRSA/CryptorRSAUtilities.swift
@@ -231,7 +231,7 @@ public extension CryptorRSA {
 			throw Error(code: ERR_STRIP_PK_HEADER, reason: "Provided public key is empty")
 		}
 		
-		var byteArray = [UInt8](keyData)
+		let byteArray = [UInt8](keyData)
 		
 		var index = 0
 		guard byteArray[index] == 0x30 else {