2018-01-03 14:43:27 -05:00

134 lines
3.1 KiB
Perl

#! c:\perl\bin\perl.exe
#-----------------------------------------------------------
# rlo.pl
# Check key/value names in a hive for RLO issue; the plugin attempts to
# show what the key/value name "looks like" via Windows-based tools,
# which interpret the RLO control charater
#
# Change history
# 20130904 - created
#
# References:
# https://blog.commtouch.com/cafe/malware/exe-read-backwards-spells-malware/
#
#
# copyright 2013 QAR, LLC
# Author: H. Carvey
#-----------------------------------------------------------
package rlo;
use strict;
my %config = (hive => "All",
hasShortDescr => 1,
hasDescr => 0,
hasRefs => 0,
osmask => 22,
category => "malware",
version => 20130904);
sub getConfig{return %config}
sub getShortDescr {
return "Parse hive, check key/value names for RLO character";
}
sub getDescr{}
sub getRefs {}
sub getHive {return $config{hive};}
sub getVersion {return $config{version};}
my $VERSION = getVersion();
my %regkeys;
sub pluginmain {
my $class = shift;
my $file = shift;
my $reg = Parse::Win32Registry->new($file);
my $root_key = $reg->get_root_key;
::logMsg("Launching rlo v.".$VERSION);
::rptMsg("rlo v.".$VERSION); # banner
::rptMsg("(".getHive().") ".getShortDescr()."\n"); # banner
my $root = $root_key->as_string();
$root = (split(/\[/,$root))[0];
chop($root);
traverse($root_key,$root);
}
sub traverse {
my $key = shift;
my $mask = shift;
my $ts = $key->get_timestamp();
my $path = $key->as_string();
$path = (split(/\[/,$path))[0];
$path =~ s/$mask//;
# print $path."\n";
my $name = $key->get_name();
if (checkRLO($name) == 1) {
my ($n,$n2) = convertRLOName($name);
$path =~ s/$name/$n/;
::rptMsg("RLO control char detected in key name: ".$path." [".$n2."]");
}
foreach my $val ($key->get_list_of_values()) {
my $val_name = $val->get_name();
if (checkRLO($val_name) == 1) {
my ($n,$n2) = convertRLOName($val_name);
::rptMsg("RLO control char detected in value name: ".$path.":".$n." [".$n2."]");
}
}
foreach my $subkey ($key->get_list_of_subkeys()) {
traverse($subkey,$mask);
}
}
sub checkRLO {
my $name = shift;
my @name_list = split(//,$name);
my ($hex,@hex_list);
my $rlo = 0;
$hex = unpack("H*",$name);
for (my $i = 0; $i < length $hex; $i+=2) {
push(@hex_list, substr($hex,$i,2));
}
if (scalar(@name_list) == scalar(@hex_list)) {
foreach my $i (0..(scalar(@name_list) - 1)) {
$rlo = 1 if (($hex_list[$i] eq "2e") && ($name_list[$i] ne "\."));
}
}
else {
return undef;
}
return $rlo;
}
sub convertRLOName {
my $name = shift;
my @name_list = split(//,$name);
my ($hex,@hex_list);
$hex = unpack("H*",$name);
for (my $i = 0; $i < length $hex; $i+=2) {
push(@hex_list, substr($hex,$i,2));
}
foreach my $i (0..(scalar(@name_list) - 1)) {
if ($hex_list[$i] eq "2e") {
$name_list[$i] = "\.";
}
}
my $str1 = join('',@name_list);
my ($f,$l) = split(/\./,$str1);
my $str2 = $f.reverse($l);
return ($str1,$str2);
}
1;