It was discovered that the Apache HTTP Server did not properly validate the request URI for proxied requests. In certain configurations, if a reverse proxy used the ProxyPassMatch directive, or if it used the RewriteRule directive with the proxy flag, a remote attacker could make the proxy connect to an arbitrary server, possibly disclosing sensitive information from internal web servers not directly accessible to the attacker. (CVE-2011-3368 __)
It was discovered that mod_proxy_ajp incorrectly returned an "Internal Server Error" response when processing certain malformed HTTP requests, which caused the back-end server to be marked as failed in configurations where mod_proxy was used in load balancer mode. A remote attacker could cause mod_proxy to not send requests to back-end AJP (Apache JServ Protocol) servers for the retry timeout period or until all back-end servers were marked as failed. (CVE-2011-3348 __)
Run yum update httpd to update your system.
i686: httpd-devel-2.2.21-1.19.amzn1.i686 httpd-tools-2.2.21-1.19.amzn1.i686 httpd-2.2.21-1.19.amzn1.i686 mod_ssl-2.2.21-1.19.amzn1.i686 httpd-debuginfo-2.2.21-1.19.amzn1.i686 noarch: httpd-manual-2.2.21-1.19.amzn1.noarch src: httpd-2.2.21-1.19.amzn1.src x86_64: mod_ssl-2.2.21-1.19.amzn1.x86_64 httpd-debuginfo-2.2.21-1.19.amzn1.x86_64 httpd-tools-2.2.21-1.19.amzn1.x86_64 httpd-devel-2.2.21-1.19.amzn1.x86_64 httpd-2.2.21-1.19.amzn1.x86_64