diff --git a/phpseclib/Common/Functions/Strings.php b/phpseclib/Common/Functions/Strings.php
index 9a424194..0f446142 100644
--- a/phpseclib/Common/Functions/Strings.php
+++ b/phpseclib/Common/Functions/Strings.php
@@ -17,6 +17,7 @@ namespace phpseclib3\Common\Functions;
 
 use ParagonIE\ConstantTime\Base64;
 use ParagonIE\ConstantTime\Base64UrlSafe;
+use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Math\BigInteger;
 use phpseclib3\Math\Common\FiniteField;
 
@@ -446,4 +447,30 @@ abstract class Strings
             sodium_bin2base64($data, SODIUM_BASE64_VARIANT_URLSAFE) :
             Base64::encode($data);
     }
+
+    /**
+     * Constant Time Hex Decoder
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function hex2bin($data)
+    {
+        return function_exists('sodium_hex2bin') ?
+            sodium_hex2bin($data) :
+            Hex::decode($data);
+    }
+
+    /**
+     * Constant Time Hex Encoder
+     *
+     * @param string $data
+     * @return string
+     */
+    public static function bin2hex($data)
+    {
+        return function_exists('sodium_bin2hex') ?
+            sodium_bin2hex($data) :
+            Hex::encode($data);
+    }
 }
diff --git a/phpseclib/Crypt/Common/Formats/Keys/PKCS1.php b/phpseclib/Crypt/Common/Formats/Keys/PKCS1.php
index 6e431022..4d9808ae 100644
--- a/phpseclib/Crypt/Common/Formats/Keys/PKCS1.php
+++ b/phpseclib/Crypt/Common/Formats/Keys/PKCS1.php
@@ -15,7 +15,6 @@ declare(strict_types=1);
 
 namespace phpseclib3\Crypt\Common\Formats\Keys;
 
-use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Crypt\AES;
 use phpseclib3\Crypt\DES;
@@ -129,7 +128,7 @@ abstract class PKCS1 extends PKCS
 
            * OpenSSL is the de facto standard.  It's utilized by OpenSSH and other projects */
         if (preg_match('#DEK-Info: (.+),(.+)#', $key, $matches)) {
-            $iv = Hex::decode(trim($matches[2]));
+            $iv = Strings::hex2bin(trim($matches[2]));
             // remove the Proc-Type / DEK-Info sections as they're no longer needed
             $key = preg_replace('#^(?:Proc-Type|DEK-Info): .*#m', '', $key);
             $ciphertext = ASN1::extractBER($key);
@@ -174,7 +173,7 @@ abstract class PKCS1 extends PKCS
         $iv = Random::string($cipher->getBlockLength() >> 3);
         $cipher->setKey(self::generateSymmetricKey($password, $iv, $cipher->getKeyLength() >> 3));
         $cipher->setIV($iv);
-        $iv = strtoupper(Hex::encode($iv));
+        $iv = strtoupper(Strings::bin2hex($iv));
         return "-----BEGIN $type PRIVATE KEY-----\r\n" .
                "Proc-Type: 4,ENCRYPTED\r\n" .
                "DEK-Info: " . $encryptionAlgorithm . ",$iv\r\n" .
diff --git a/phpseclib/Crypt/Common/Formats/Keys/PuTTY.php b/phpseclib/Crypt/Common/Formats/Keys/PuTTY.php
index 17e3f9ed..8d49ce13 100644
--- a/phpseclib/Crypt/Common/Formats/Keys/PuTTY.php
+++ b/phpseclib/Crypt/Common/Formats/Keys/PuTTY.php
@@ -17,7 +17,6 @@ declare(strict_types=1);
 
 namespace phpseclib3\Crypt\Common\Formats\Keys;
 
-use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Crypt\AES;
 use phpseclib3\Crypt\Hash;
@@ -73,7 +72,7 @@ abstract class PuTTY
         $sequence = 0;
         while (strlen($symkey) < $length) {
             $temp = pack('Na*', $sequence++, $password);
-            $symkey .= Hex::decode(sha1($temp));
+            $symkey .= Strings::hex2bin(sha1($temp));
         }
         return substr($symkey, 0, $length);
     }
@@ -213,7 +212,7 @@ abstract class PuTTY
                         $memory = trim(preg_replace('#Argon2-Memory: (\d+)#', '$1', $key[$offset++]));
                         $passes = trim(preg_replace('#Argon2-Passes: (\d+)#', '$1', $key[$offset++]));
                         $parallelism = trim(preg_replace('#Argon2-Parallelism: (\d+)#', '$1', $key[$offset++]));
-                        $salt = Hex::decode(trim(preg_replace('#Argon2-Salt: ([0-9a-f]+)#', '$1', $key[$offset++])));
+                        $salt = Strings::hex2bin(trim(preg_replace('#Argon2-Salt: ([0-9a-f]+)#', '$1', $key[$offset++])));
 
                         extract(self::generateV3Key($password, $flavour, (int)$memory, (int)$passes, $salt));
 
@@ -248,7 +247,7 @@ abstract class PuTTY
         $source .= Strings::packSSH2('s', $private);
 
         $hmac = trim(preg_replace('#Private-MAC: (.+)#', '$1', $key[$offset + $privateLength]));
-        $hmac = Hex::decode($hmac);
+        $hmac = Strings::hex2bin($hmac);
 
         if (!hash_equals($hash->hash($source), $hmac)) {
             throw new \UnexpectedValueException('MAC validation error');
@@ -306,7 +305,7 @@ abstract class PuTTY
                     $key .= "Argon2-Memory: 8192\r\n";
                     $key .= "Argon2-Passes: 13\r\n";
                     $key .= "Argon2-Parallelism: 1\r\n";
-                    $key .= "Argon2-Salt: " . Hex::encode($salt) . "\r\n";
+                    $key .= "Argon2-Salt: " . Strings::bin2hex($salt) . "\r\n";
                     extract(self::generateV3Key($password, 'Argon2id', 8192, 13, $salt));
 
                     $hash = new Hash('sha256');
@@ -332,7 +331,7 @@ abstract class PuTTY
         $private = Strings::base64_encode($private);
         $key .= 'Private-Lines: ' . ((strlen($private) + 63) >> 6) . "\r\n";
         $key .= chunk_split($private, 64);
-        $key .= 'Private-MAC: ' . Hex::encode($hash->hash($source)) . "\r\n";
+        $key .= 'Private-MAC: ' . Strings::bin2hex($hash->hash($source)) . "\r\n";
 
         return $key;
     }
diff --git a/phpseclib/Crypt/EC/Formats/Keys/Common.php b/phpseclib/Crypt/EC/Formats/Keys/Common.php
index 0489263e..b2130651 100644
--- a/phpseclib/Crypt/EC/Formats/Keys/Common.php
+++ b/phpseclib/Crypt/EC/Formats/Keys/Common.php
@@ -15,7 +15,6 @@ declare(strict_types=1);
 
 namespace phpseclib3\Crypt\EC\Formats\Keys;
 
-use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Crypt\EC\BaseCurves\Base as BaseCurve;
 use phpseclib3\Crypt\EC\BaseCurves\Binary as BinaryCurve;
@@ -249,8 +248,8 @@ trait Common
                     $curve->setModulo(...$modulo);
                     $len = ceil($modulo[0] / 8);
                     $curve->setCoefficients(
-                        Hex::encode($data['curve']['a']),
-                        Hex::encode($data['curve']['b'])
+                        Strings::bin2hex($data['curve']['a']),
+                        Strings::bin2hex($data['curve']['b'])
                     );
                     $point = self::extractPoint("\0" . $data['base'], $curve);
                     $curve->setBasePoint(...$point);
@@ -294,7 +293,7 @@ trait Common
         // the first byte of a bit string represents the number of bits in the last byte that are to be ignored but,
         // currently, bit strings wanting a non-zero amount of bits trimmed are not supported
         if (($val = Strings::shift($str)) != "\0") {
-            throw new \UnexpectedValueException('extractPoint expects the first byte to be null - not ' . Hex::encode($val));
+            throw new \UnexpectedValueException('extractPoint expects the first byte to be null - not ' . Strings::bin2hex($val));
         }
         if ($str == "\0") {
             return [];
@@ -312,7 +311,7 @@ trait Common
             preg_match("#(.)(.{{$order}})(.{{$order}})#s", $str, $matches);
             [, $w, $x, $y] = $matches;
             if ($w != "\4") {
-                throw new \UnexpectedValueException('The first byte of an uncompressed point should be 04 - not ' . Hex::encode($val));
+                throw new \UnexpectedValueException('The first byte of an uncompressed point should be 04 - not ' . Strings::bin2hex($val));
             }
             $point = [
                 $curve->convertInteger(new BigInteger($x, 256)),
diff --git a/phpseclib/File/X509.php b/phpseclib/File/X509.php
index cf11003b..fc12dd30 100644
--- a/phpseclib/File/X509.php
+++ b/phpseclib/File/X509.php
@@ -26,7 +26,6 @@ declare(strict_types=1);
 
 namespace phpseclib3\File;
 
-use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Crypt\Common\PrivateKey;
 use phpseclib3\Crypt\Common\PublicKey;
@@ -1772,7 +1771,7 @@ class X509
                 $hash = new Hash('sha1');
                 $hash = $hash->hash($dn);
                 extract(unpack('Vhash', $hash));
-                return strtolower(Hex::encode(pack('N', $hash)));
+                return strtolower(Strings::bin2hex(pack('N', $hash)));
         }
 
         // Default is to return a string.
diff --git a/phpseclib/Math/BigInteger/Engines/BCMath.php b/phpseclib/Math/BigInteger/Engines/BCMath.php
index def5a8f4..3b6616b9 100644
--- a/phpseclib/Math/BigInteger/Engines/BCMath.php
+++ b/phpseclib/Math/BigInteger/Engines/BCMath.php
@@ -15,7 +15,7 @@ declare(strict_types=1);
 
 namespace phpseclib3\Math\BigInteger\Engines;
 
-use ParagonIE\ConstantTime\Hex;
+use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Exception\BadConfigurationException;
 
 /**
@@ -100,7 +100,7 @@ class BCMath extends Engine
                 break;
             case 16:
                 $x = (strlen($this->value) & 1) ? '0' . $this->value : $this->value;
-                $temp = new self(Hex::decode($x), 256);
+                $temp = new self(Strings::hex2bin($x), 256);
                 $this->value = $this->is_negative ? '-' . $temp->value : $temp->value;
                 $this->is_negative = false;
                 break;
diff --git a/phpseclib/Math/BigInteger/Engines/Engine.php b/phpseclib/Math/BigInteger/Engines/Engine.php
index 7b8bf6f6..dcbffc63 100644
--- a/phpseclib/Math/BigInteger/Engines/Engine.php
+++ b/phpseclib/Math/BigInteger/Engines/Engine.php
@@ -15,7 +15,6 @@ declare(strict_types=1);
 
 namespace phpseclib3\Math\BigInteger\Engines;
 
-use ParagonIE\ConstantTime\Hex;
 use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Crypt\Random;
 use phpseclib3\Exception\BadConfigurationException;
@@ -173,7 +172,7 @@ abstract class Engine implements \JsonSerializable
                 $is_negative = false;
                 if ($base < 0 && hexdec($x[0]) >= 8) {
                     $this->is_negative = $is_negative = true;
-                    $x = Hex::encode(~Hex::decode($x));
+                    $x = Strings::bin2hex(~Strings::hex2bin($x));
                 }
 
                 $this->value = $x;
@@ -267,7 +266,7 @@ abstract class Engine implements \JsonSerializable
      */
     public function toHex(bool $twos_compliment = false): string
     {
-        return Hex::encode($this->toBytes($twos_compliment));
+        return Strings::bin2hex($this->toBytes($twos_compliment));
     }
 
     /**
diff --git a/phpseclib/Math/BigInteger/Engines/PHP.php b/phpseclib/Math/BigInteger/Engines/PHP.php
index 6fcf472e..77a19281 100644
--- a/phpseclib/Math/BigInteger/Engines/PHP.php
+++ b/phpseclib/Math/BigInteger/Engines/PHP.php
@@ -15,7 +15,7 @@ declare(strict_types=1);
 
 namespace phpseclib3\Math\BigInteger\Engines;
 
-use ParagonIE\ConstantTime\Hex;
+use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Exception\BadConfigurationException;
 
 /**
@@ -94,7 +94,7 @@ abstract class PHP extends Engine
         switch (abs($base)) {
             case 16:
                 $x = (strlen($this->value) & 1) ? '0' . $this->value : $this->value;
-                $temp = new static(Hex::decode($x), 256);
+                $temp = new static(Strings::hex2bin($x), 256);
                 $this->value = $temp->value;
                 break;
             case 10:
diff --git a/phpseclib/Math/BinaryField/Integer.php b/phpseclib/Math/BinaryField/Integer.php
index b6bb12c8..5b69bbe0 100644
--- a/phpseclib/Math/BinaryField/Integer.php
+++ b/phpseclib/Math/BinaryField/Integer.php
@@ -22,7 +22,7 @@ declare(strict_types=1);
 
 namespace phpseclib3\Math\BinaryField;
 
-use ParagonIE\ConstantTime\Hex;
+use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Math\BigInteger;
 use phpseclib3\Math\BinaryField;
 use phpseclib3\Math\Common\FiniteField\Integer as Base;
@@ -448,7 +448,7 @@ class Integer extends Base
      */
     public function toHex(): string
     {
-        return Hex::encode($this->toBytes());
+        return Strings::bin2hex($this->toBytes());
     }
 
     /**
diff --git a/phpseclib/Math/PrimeField/Integer.php b/phpseclib/Math/PrimeField/Integer.php
index 3927dffd..c1fd0a81 100644
--- a/phpseclib/Math/PrimeField/Integer.php
+++ b/phpseclib/Math/PrimeField/Integer.php
@@ -14,7 +14,7 @@ declare(strict_types=1);
 
 namespace phpseclib3\Math\PrimeField;
 
-use ParagonIE\ConstantTime\Hex;
+use phpseclib3\Common\Functions\Strings;
 use phpseclib3\Math\BigInteger;
 use phpseclib3\Math\Common\FiniteField\Integer as Base;
 
@@ -302,7 +302,7 @@ class Integer extends Base
      */
     public function toHex(): string
     {
-        return Hex::encode($this->toBytes());
+        return Strings::bin2hex($this->toBytes());
     }
 
     /**