The web server running on the remote host is affected by a denial of service vulnerability.
The version of Apache HTTP Server running on the remote host is affected by a denial of service vulnerability. Making a series of HTTP requests with overlapping ranges in the Range or Request-Range request headers can result in memory and CPU exhaustion. A remote, unauthenticated attacker could exploit this to make the system unresponsive. Exploit code is publicly available and attacks have reportedly been observed in the wild.
Upgrade to Apache httpd 2.2.21 or later. Alternatively, apply one of the workarounds in Apache's advisories for CVE-2011-3192. Version 2.2.20 fixed the issue, but it also introduced a regression. If the host is running a web server based on Apache httpd, contact the vendor for a fix.