zeek/scripts/policy/frameworks/intel/seen/http-headers.zeek
Robin Sommer 07045ec254
Fix host header normalization in intel framework.
The way we were splitting off ports from host names could fail for IPv6
addresses.

Closes #1844.
2021-12-21 21:54:47 +01:00

55 lines
1.4 KiB
Text

@load base/frameworks/intel
@load ./where-locations
@load base/utils/addrs
event http_header(c: connection, is_orig: bool, name: string, value: string)
{
if ( is_orig )
{
switch ( name )
{
case "HOST":
# Remove the occasional port value that shows up here.
local host = gsub(value, /:[[:digit:]]+$/, "");
if ( is_valid_ip(host) )
Intel::seen([$host=to_addr(host),
$indicator_type=Intel::ADDR,
$conn=c,
$where=HTTP::IN_HOST_HEADER]);
else
Intel::seen([$indicator=host,
$indicator_type=Intel::DOMAIN,
$conn=c,
$where=HTTP::IN_HOST_HEADER]);
break;
case "REFERER":
Intel::seen([$indicator=sub(value, /^.*:\/\//, ""),
$indicator_type=Intel::URL,
$conn=c,
$where=HTTP::IN_REFERRER_HEADER]);
break;
case "X-FORWARDED-FOR":
if ( is_valid_ip(value) )
{
local addrs = extract_ip_addresses(value);
for ( i in addrs )
{
Intel::seen([$host=to_addr(addrs[i]),
$indicator_type=Intel::ADDR,
$conn=c,
$where=HTTP::IN_X_FORWARDED_FOR_HEADER]);
}
}
break;
case "USER-AGENT":
Intel::seen([$indicator=value,
$indicator_type=Intel::SOFTWARE,
$conn=c,
$where=HTTP::IN_USER_AGENT_HEADER]);
break;
}
}
}