Shell characters injections, buffer overflows, format string vulnerabilities, race conditions, etc.
vulners.com/securityvulns/securityvulns:doc:16875
vulners.com/securityvulns/securityvulns:doc:16876
vulners.com/securityvulns/securityvulns:doc:16877
vulners.com/securityvulns/securityvulns:doc:16878