local http = require "http"
local shortport = require "shortport"
local stdnse = require "stdnse"
local vulns = require "vulns"
description = [[
Detects a denial of service vulnerability in the way the Apache web server
handles requests for multiple overlapping/simple ranges of a page.
References:
* http://seclists.org/fulldisclosure/2011/Aug/175
* http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3192
* http://nessus.org/plugins/index.php?view=single&id=55976
]]
---
-- @usage
-- nmap --script http-vuln-cve2011-3192.nse [--script-args http-vuln-cve2011-3192.hostname=nmap.scanme.org] -pT:80,443 <host>
--
-- @output
-- Host script results:
-- | http-vuln-cve2011-3192:
-- | VULNERABLE:
-- | Apache byterange filter DoS
-- | State: VULNERABLE
-- | IDs: CVE:CVE-2011-3192 OSVDB:74721
-- | Description:
-- | The Apache web server is vulnerable to a denial of service attack when numerous
-- | overlapping byte ranges are requested.
-- | Disclosure date: 2011-08-19
-- | References:
-- | http://seclists.org/fulldisclosure/2011/Aug/175
-- | http://nessus.org/plugins/index.php?view=single&id=55976
-- | http://osvdb.org/74721
-- |_ http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3192
--
-- @args http-vuln-cve2011-3192.hostname Define the host name to be used in the HEAD request sent to the server
-- @args http-vuln-cve2011-3192.path Define the request path
-- changelog
-- 2011-08-29 Duarte Silva <duarte.silva@serializing.me>
-- - Removed the "Accept-Encoding" HTTP header
-- - Removed response header printing
-- * Changes based on Henri Doreau and David Fifield sugestions
-- 2011-08-20 Duarte Silva <duarte.silva@serializing.me>
-- * First version ;)
-- 2011-11-07 Henri Doreau
-- * Use the vulns library to report results
-----------------------------------------------------------------------
author = "Duarte Silva <duarte.silva@serializing.me>"
license = "Same as Nmap--See http://nmap.org/book/man-legal.html"
categories = {"vuln", "safe"}
portrule = shortport.http
action = function(host, port)
local vuln = {
title = 'Apache byterange filter DoS',
state = vulns.STATE.NOT_VULN, -- default
IDS = {CVE = 'CVE-2011-3192', OSVDB = '74721'},
description = [[
The Apache web server is vulnerable to a denial of service attack when numerous
overlapping byte ranges are requested.]],
references = {
'http://seclists.org/fulldisclosure/2011/Aug/175',
'http://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2011-3192',
'http://nessus.org/plugins/index.php?view=single&id=55976',
},
dates = {
disclosure = {year = '2011', month = '08', day = '19'},
},
}
local vuln_report = vulns.Report:new(SCRIPT_NAME, host, port)
local hostname, path = stdnse.get_script_args('http-vuln-cve2011-3192.hostname',
'http-vuln-cve2011-3192.path')
if not path then
path = '/'
stdnse.print_debug(1, "Setting the request path to '/' since 'http-vuln-cve2011-3192.path' argument is missing.")
end
-- This first request will try to get a code 206 reply from the server by
-- sending the innocuous header "Range: byte=0-100" in order to detect
-- whether this functionality is available or not.
local request_opts = {
header = {
Range = "bytes=0-100",
Connection = "close"
},
bypass_cache = true
}
if hostname then
request_opts.header.Host = hostname
end
local response = http.head(host, port, path, request_opts)
if not response.status then
stdnse.print_debug(1, "%s: Functionality check HEAD request failed for %s (with path '%s').",
SCRIPT_NAME, hostname or host.ip, path)
elseif response.status == 206 then
-- The server handle range requests. Now try to request 11 ranges (one more
-- than allowed).
-- Vulnerable servers will reply with another code 206 response. Patched
-- ones will return a code 200.
request_opts.header.Range = "bytes=1-0,0-0,1-1,2-2,3-3,4-4,5-5,6-6,7-7,8-8,9-9,10-10"
response = http.head(host, port, path, request_opts)
if not response.status then
stdnse.print_debug(1, "%s: Invalid response from server to the vulnerability check",
SCRIPT_NAME)
elseif response.status == 206 then
vuln.state = vulns.STATE.VULN
else
stdnse.print_debug(1, "%s: Server isn't vulnerable (%i status code)",
SCRIPT_NAME, response.status)
end
else
stdnse.print_debug(1, "%s: Server ignores the range header (%i status code)",
SCRIPT_NAME, response.status)
end
return vuln_report:make_output(vuln)
end
@KyuuKazami