PHP contains a flaw that allows an attacker to bypass protection against HTTP response splitting attacks. This flaw exists because the sapi_header_op function in main/SAPI.c does not properly handle %0D sequences. This may allow an attacker to bypass protection against the insertion of arbitrary HTTP headers, which are included in a response sent to the server. If an application does not properly filter such a request, it could be used to inject additional headers that manipulate cookies, authentication status, or more.
Remote / Network Access
Loss of Integrity
Upgrade to version 5.3.11 or higher, as it has been reported to fix this vulnerability. An upgrade is required as there are no known workarounds.