diff --git a/.travis.yml b/.travis.yml
index 367d99f..dc1b6ae 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -15,7 +15,6 @@ matrix:
 
 before_install:
    - export ALLOW_FAILURE=1; if [ "$TRAVIS_PHP_VERSION" != "hhvm" ] && [ "$TRAVIS_PHP_VERSION" != "nightly" ]; then export ALLOW_FAILURE=0; fi
-   - if [ "$TRAVIS_PHP_VERSION" == "7.2" ]; then yes '' | pecl install mcrypt-1.0.2; fi
 
 install:
   - composer self-update
diff --git a/composer.json b/composer.json
index 02b2881..635db3c 100644
--- a/composer.json
+++ b/composer.json
@@ -16,10 +16,9 @@
         "source": "https://github.com/robinpowered/php-ntlm"
     },
     "require": {
-        "php-64bit": ">=7.1.0"
+        "php-64bit": ">=8.3.0"
     },
     "require-dev": {
-        "ext-mcrypt": "*",
         "ext-hash": "*",
         "ext-mbstring": "*",
         "ext-iconv": "*",
diff --git a/src/Robin/Ntlm/Crypt/Des/McryptDesEncrypter.php b/src/Robin/Ntlm/Crypt/Des/McryptDesEncrypter.php
deleted file mode 100644
index 7b0d205..0000000
--- a/src/Robin/Ntlm/Crypt/Des/McryptDesEncrypter.php
+++ /dev/null
@@ -1,70 +0,0 @@
-<?php
-/**
- * Robin NTLM
- *
- * @copyright 2019 Robin Powered, Inc.
- * @link https://robinpowered.com/
- */
-
-namespace Robin\Ntlm\Crypt\Des;
-
-use InvalidArgumentException;
-use Robin\Ntlm\Crypt\CipherMode;
-use Robin\Ntlm\Crypt\Exception\CryptographicFailureException;
-
-/**
- * @deprecated Mcrypt has been deprecated from the core PHP library. Use
- * {@see OpenSslDesEncrypter} as an alternative.
- * @link https://php.net/manual/en/migration72.other-changes.php#migration72.other-changes.mcrypt
- *
- * An engine used to encrypt data using the DES standard algorithm and
- * implemented using the PHP "mcrypt" extension.
- *
- * @link http://php.net/mcrypt
- */
-class McryptDesEncrypter extends AbstractDesEncrypter implements DesEncrypterInterface
-{
-
-    /**
-     * Properties
-     */
-
-    /**
-     * A map of {@link CipherMode}s to the "mcrypt" extension equivalents.
-     */
-    private static $cipher_mode_map = [
-        CipherMode::CBC => MCRYPT_MODE_CBC,
-        CipherMode::CFB => MCRYPT_MODE_CFB,
-        CipherMode::ECB => MCRYPT_MODE_ECB,
-        CipherMode::OFB => MCRYPT_MODE_OFB,
-    ];
-
-
-    /**
-     * Methods
-     */
-
-    /**
-     * {@inheritDoc}
-     */
-    public function encrypt($key, $data, $mode, $initialization_vector)
-    {
-        if (isset(self::$cipher_mode_map[$mode])) {
-            $mode = self::$cipher_mode_map[$mode];
-        } else {
-            throw new InvalidArgumentException('Unknown cipher mode "'. $mode .'"');
-        }
-
-        $key = $this->processKey($key);
-
-        $encrypted = mcrypt_encrypt(MCRYPT_DES, $key, $data, $mode, $initialization_vector);
-
-        if (false === $encrypted) {
-            throw CryptographicFailureException::forReasonCode(
-                CryptographicFailureException::CODE_FOR_ENCRYPTION_FAILURE
-            );
-        }
-
-        return $encrypted;
-    }
-}
diff --git a/src/Robin/Ntlm/Crypt/Random/McryptRandomByteGenerator.php b/src/Robin/Ntlm/Crypt/Random/McryptRandomByteGenerator.php
deleted file mode 100644
index d1ca9f6..0000000
--- a/src/Robin/Ntlm/Crypt/Random/McryptRandomByteGenerator.php
+++ /dev/null
@@ -1,90 +0,0 @@
-<?php
-/**
- * Robin NTLM
- *
- * @copyright 2016 Robin Powered, Inc.
- * @link https://robinpowered.com/
- */
-
-namespace Robin\Ntlm\Crypt\Random;
-
-use Robin\Ntlm\Crypt\Exception\CryptographicFailureException;
-
-/**
- * A cryptographically secure random byte generator implemented using the PHP
- * "mcrypt" extension.
- *
- * @link http://php.net/mcrypt
- * @deprecated This implementation is deprecated, as the mcrypt library
- *   is abandoned. Use {@link NativeRandomByteGenerator} instead.
- *   More info: https://github.com/robinpowered/php-ntlm/pull/1
- * @todo Mcrypt is abandoned and this should be removed in a future version.
- */
-class McryptRandomByteGenerator implements RandomByteGeneratorInterface
-{
-
-    /**
-     * Constants
-     */
-
-    /**
-     * The default source of randomness.
-     *
-     * @type int
-     */
-    const DEFAULT_SOURCE = MCRYPT_DEV_URANDOM;
-
-
-    /**
-     * Properties
-     */
-
-    /**
-     * The `mcrypt_create_iv` compatible source.
-     *
-     * @link http://php.net/manual/en/mcrypt.constants.php
-     * @type int
-     */
-    private $source = self::DEFAULT_SOURCE;
-
-
-    /**
-     * Methods
-     */
-
-    /**
-     * Constructor
-     *
-     * @link http://php.net/manual/en/mcrypt.constants.php
-     * @param int $source The `mcrypt_create_iv` compatible source of
-     *   cryptographically secure randomness. Defaults to self::DEFAULT_SOURCE.
-     */
-    public function __construct($source = self::DEFAULT_SOURCE)
-    {
-        $this->source = $source;
-    }
-
-    /**
-     * {@inheritDoc}
-     *
-     * @deprecated This implementation is deprecated, as the mcrypt
-     *   library is abandoned. Use {@link NativeRandomByteGenerator} instead.
-     */
-    public function generate($size)
-    {
-        trigger_error(
-            'This implementation is deprecated, as the mcrypt library is abandoned',
-            E_USER_DEPRECATED
-        );
-
-        $generated = mcrypt_create_iv($size, $this->source);
-
-        if (false === $generated || strlen($generated) !== $size) {
-            throw CryptographicFailureException::forReasonCode(
-                CryptographicFailureException::CODE_FOR_RANDOM_DATA_GENERATION_FAILURE
-            );
-        }
-
-        return $generated;
-    }
-}