codeql/csharp/ql/test/query-tests/Security Features/CWE-502/UnsafeDeserialization/BinaryFormatterBad.cs

using System.Runtime.Serialization.Formatters.Binary;
using System.IO;

class BadBinaryFormatter
{
    public static object Deserialize(Stream s)
    {
        var ds = new BinaryFormatter();
        // BAD
        return ds.Deserialize(s); // $ Alert[cs/unsafe-deserialization]
    }
}