garbage characters at the end of string

Server: DB2 7.1.0
Client: 11.5.4.0
PHP: 8.2.17
pdo_ibm: latest main branch

There is no problem with the following command line:
db2 "SELECT ONAME from MYTABLE where ID='590'"

However, retrieving data via PHP like this:

$dbh = new PDO($dsn);
$result = $dbh->query("SELECT ONAME from MYTABLE where ID='590'");
foreach($result as $row){
    echo  $row[0];
}

At the end of the string, there is a 0x00 and some other random characters.

trim($row[0],"\x0")
can remove the trash characters.

Reproduce the issue with the shown PHP PDO query against DB2 and compare its returned string with the command-line result. Start by tracing how pdo_ibm handles returned string values; done means the PHP result no longer contains the trailing 0x00 or random characters while preserving the actual value.