source: https://www.securityfocus.com/bid/32909/info
GNU Classpath is prone to a weakness that may result in weaker cryptographic security because its psuedo-random number generator (PRNG) lacks entropy.
Attackers may leverage this issue to obtain sensitive information that can lead to further attacks.
Classpath 0.97.2 is vulnerable; other versions may also be affected.
import gnu.java.security.util.PRNG;
class PRNGTest {
public static void main(String args[])
{
long t = System.currentTimeMillis();
System.out.println("Time in ms is " + t);
PRNG prng = PRNG.getInstance();
byte buffer[] = new byte[40];
prng.nextBytes(buffer, 0, buffer.length);
for(int i = 0; i != buffer.length; ++i)
{
// There must be an easier way to do this (right?)
int intval = buffer[i];
if(intval <= 0)
intval += 256;
String s = Integer.toHexString(intval);
if(s.length() == 1)
s = "0" + s;
System.out.print(s);
}
System.out.println("");
}
};