The mod_headers module in the Apache HTTP Server 2.2.22 allows remote attackers to bypass RequestHeader unset directives by placing a header in the trailer portion of data sent with chunked transfer coding. NOTE: the vendor states this is not a security issue in httpd as such. LIN8-2221 http://web.nvd.nist.gov/view/vuln/detail?vulnId=CVE-2013-5704