Buffer underflow in the header function in PHP 5.2.0 allows context-dependent attackers to execute arbitrary code by passing an all-whitespace string to this function, which causes it to write '\0' characters in whitespace that precedes the string.
Exploitability
AV:NAC:MAu:NImpact
C:PI:PA:P6.8/AV:N/AC:M/Au:N/C:P/I:P/A:P