profttp 1.3.5b injecting extra characters in wordpress files when uploading

I been trying to find out why when I upload a brand new wordpress install using ProFTPd 1.3.5b the files get injected with extra characters that aren't part of the file.

It only happens to /wp-includes/functions.php from what I can see

these are the injections i have caught so far

line ~569:

foreach ( $pung as $link_test ) {
        if ( ! in_array( $link_test, $post_links_temp ) ) { // link no longer in post
            $mids = $wpdb->get_col( $wpdb->prepare("SELECT meta_id FROM $wpdb->postmeta WHERE post_id = %d AND meta_key = 'enclosure' AND meta_value LIKE %s", $post_ID, $wpdb->esc_like( $link_test ) . '%') );
t // <--- this "t" is added
            foreach ( $mids as $mid )
                delete_metadata_by_mid( 'post', $mid );
        }
    }

line ~1780

function win_is_writable( $path ) {

    if ( $path[strlen( $path ) - 1] == '/' ) { // if it looks like a directory, check a random file within the directory
        return win_is_writable( $path . uniqid( mt_rand() ) . '.tmp');
    } elseif ( is_dir( $path ) ) { // If it's a directory (and not a file) check a random file within the directory
        return win_is_writable( $path . '/' . uniqid( mt_rand() ) . '.tmp' );
    }
    // check tmp file for read/write capabilities
    $should_delete_tmp_file = !file_exists( $path );
    $f = @fopen( $path, 'a' );
    if ( $f === false )
        return false;
    fclose( $f );
    if ( $should_delete_tmp_file )
        unlink( $path );
    return true;
}
e // <-- this "e" is added

line ~2677

        .button:active {
            background: #eee;
            border-color: #999;
            -webkit-box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
            box-shadow: inset 0 2px 5px -3px rgba( 0, 0, 0, 0.5 );
            -webkit-transform: translateY(1px);
            -ms-transform: translateY(1px);
            transform: translateY(1px);
        }
        o /* <-- this "o" is added */

        <?php
        if ( 'rtl' == $text_direction ) {
            echo 'body { font-family: Tahoma, Arial; }';
        }

line ~3332

function wp_list_filter( $list, $args = array(), $operator = 'AND' ) {
    if ( ! is_array( $list ) )
        return array();

    if ( empty( $args ) )
        return $list;

    $operator = strtoupper( $operator );
    $count = count( $args );
    o // <-- this "o" is added
    $filtered = array();

    foreach ( $list as $key => $obj ) {
        $to_match = (array) $obj;

        $matched = 0;
        foreach ( $args as $m_key => $m_value ) {
            if ( array_key_exists( $m_key, $to_match ) && $m_value == $to_match[ $m_key ] )
                $matched++;
        }

        if ( ( 'AND' == $operator && $matched == $count )
            || ( 'OR' == $operator && $matched > 0 )
            || ( 'NOT' == $operator && 0 == $matched ) ) {
            $filtered[$key] = $obj;
        }
    }

    return $filtered;
}

line ~3719

function _deprecated_argument( $function, $version, $message = null ) {
    i // <-- this "i" is added

    /**
     * Fires when a deprecated argument is called.
     *
     * @since 3.0.0
     *
     * @param string $function The function that was called.
     * @param string $message  A message regarding the change.
     * @param string $version  The version of WordPress that deprecated the argument used.
     */
    do_action( 'deprecated_argument_run', $function, $message, $version );

    /**
     * Filter whether to trigger an error for deprecated arguments.
     *
     * @since 3.0.0
     *
     * @param bool $trigger Whether to trigger the error for deprecated arguments. Default true.
     */
    if ( WP_DEBUG && apply_filters( 'deprecated_argument_trigger_error', true ) ) {
        if ( function_exists( '__' ) ) {
            if ( ! is_null( $message ) )
                trigger_error( sprintf( __('%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s! %3$s'), $function, $version, $message ) );
            else
                trigger_error( sprintf( __('%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s with no alternative available.'), $function, $version ) );
        } else {
            if ( ! is_null( $message ) )
                trigger_error( sprintf( '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s! %3$s', $function, $version, $message ) );
            else
                trigger_error( sprintf( '%1$s was called with an argument that is <strong>deprecated</strong> since version %2$s with no alternative available.', $function, $version ) );
        }
    }
}

I'm connected via port 21, regular ftp (not sftp or tls). Also not using passive mode.