From: Michael Tremer <michael.tremer@ipfire.org>
Date: Wed, 14 Jun 2017 11:58:12 +0000 (+0100)
Subject: ids.cgi: Fix remote command execution vulnerability
X-Git-Tag: v2.19-core112~28^2~15
X-Git-Url: http://git.ipfire.org/?a=commitdiff_plain;h=a9a91e5fa713c14f59d20228c228f0e67c4365a8;p=ipfire-2.x.git

ids.cgi: Fix remote command execution vulnerability

The OINKCODE variable was only validated for proper input
when the Save button was clicked.

Did the user demand to download new rules instead, the
content of that variable was not being validated (again)
and was passed to wget on the shell.

This was done with privileges of the "nobody" user.

Fixes #11401

Signed-off-by: Michael Tremer <michael.tremer@ipfire.org>
---

diff --git a/html/cgi-bin/ids.cgi b/html/cgi-bin/ids.cgi
index fbd1f13b26..3d9519757d 100644
--- a/html/cgi-bin/ids.cgi
+++ b/html/cgi-bin/ids.cgi
@@ -253,99 +253,94 @@ if (-e "/etc/snort/snort.conf") {
 
 #######################  End added for snort rules control  #################################
 
-if ($snortsettings{'RULES'} eq 'subscripted') {
-	$url=" https://www.snort.org/rules/snortrules-snapshot-2990.tar.gz?oinkcode=$snortsettings{'OINKCODE'}";
-} elsif ($snortsettings{'RULES'} eq 'registered') {
-	$url=" https://www.snort.org/rules/snortrules-snapshot-2990.tar.gz?oinkcode=$snortsettings{'OINKCODE'}";
-} elsif ($snortsettings{'RULES'} eq 'community') {
-	$url=" https://www.snort.org/rules/community";
-} else {
-	$url="http://rules.emergingthreats.net/open/snort-2.9.0/emerging.rules.tar.gz";
+if ($snortsettings{'OINKCODE'} ne "") {
+	$errormessage = $Lang::tr{'invalid input for oink code'} unless ($snortsettings{'OINKCODE'} =~ /^[a-z0-9]+$/);
 }
 
-if ($snortsettings{'ACTION'} eq $Lang::tr{'save'} && $snortsettings{'ACTION2'} eq "snort" )
-{
-	$errormessage = $Lang::tr{'invalid input for oink code'} unless (
-	    ($snortsettings{'OINKCODE'} =~ /^[a-z0-9]+$/)  ||
-	    ($snortsettings{'RULES'} eq 'nothing' ) ||
-	    ($snortsettings{'RULES'} eq 'emerging' ) ||
-	    ($snortsettings{'RULES'} eq 'community' ));
-
-	&General::writehash("${General::swroot}/snort/settings", \%snortsettings);
-	if ($snortsettings{'ENABLE_SNORT'} eq 'on')
-	{
-		system ('/usr/bin/touch', "${General::swroot}/snort/enable");
+if (!$errormessage) {
+	if ($snortsettings{'RULES'} eq 'subscripted') {
+		$url=" https://www.snort.org/rules/snortrules-snapshot-2990.tar.gz?oinkcode=$snortsettings{'OINKCODE'}";
+	} elsif ($snortsettings{'RULES'} eq 'registered') {
+		$url=" https://www.snort.org/rules/snortrules-snapshot-2990.tar.gz?oinkcode=$snortsettings{'OINKCODE'}";
+	} elsif ($snortsettings{'RULES'} eq 'community') {
+		$url=" https://www.snort.org/rules/community";
 	} else {
-		unlink "${General::swroot}/snort/enable";
-	}
-	if ($snortsettings{'ENABLE_SNORT_GREEN'} eq 'on')
-	{
-		system ('/usr/bin/touch', "${General::swroot}/snort/enable_green");
-	} else {
-		unlink "${General::swroot}/snort/enable_green";
-	}
-	if ($snortsettings{'ENABLE_SNORT_BLUE'} eq 'on')
-	{
-		system ('/usr/bin/touch', "${General::swroot}/snort/enable_blue");
-	} else {
-		unlink "${General::swroot}/snort/enable_blue";
-	}
-	if ($snortsettings{'ENABLE_SNORT_ORANGE'} eq 'on')
-	{
-		system ('/usr/bin/touch', "${General::swroot}/snort/enable_orange");
-	} else {
-		unlink "${General::swroot}/snort/enable_orange";
-	}
-	if ($snortsettings{'ENABLE_PREPROCESSOR_HTTP_INSPECT'} eq 'on')
-	{
-		system ('/usr/bin/touch', "${General::swroot}/snort/enable_preprocessor_http_inspect");
-	} else {
-		unlink "${General::swroot}/snort/enable_preprocessor_http_inspect";
+		$url="http://rules.emergingthreats.net/open/snort-2.9.0/emerging.rules.tar.gz";
 	}
 
-	system('/usr/local/bin/snortctrl restart >/dev/null');
+	if ($snortsettings{'ACTION'} eq $Lang::tr{'save'} && $snortsettings{'ACTION2'} eq "snort" ) {
+		&General::writehash("${General::swroot}/snort/settings", \%snortsettings);
+		if ($snortsettings{'ENABLE_SNORT'} eq 'on')
+		{
+			system ('/usr/bin/touch', "${General::swroot}/snort/enable");
+		} else {
+			unlink "${General::swroot}/snort/enable";
+		}
+		if ($snortsettings{'ENABLE_SNORT_GREEN'} eq 'on')
+		{
+			system ('/usr/bin/touch', "${General::swroot}/snort/enable_green");
+		} else {
+			unlink "${General::swroot}/snort/enable_green";
+		}
+		if ($snortsettings{'ENABLE_SNORT_BLUE'} eq 'on')
+		{
+			system ('/usr/bin/touch', "${General::swroot}/snort/enable_blue");
+		} else {
+			unlink "${General::swroot}/snort/enable_blue";
+		}
+		if ($snortsettings{'ENABLE_SNORT_ORANGE'} eq 'on')
+		{
+			system ('/usr/bin/touch', "${General::swroot}/snort/enable_orange");
+		} else {
+			unlink "${General::swroot}/snort/enable_orange";
+		}
+		if ($snortsettings{'ENABLE_PREPROCESSOR_HTTP_INSPECT'} eq 'on')
+		{
+			system ('/usr/bin/touch', "${General::swroot}/snort/enable_preprocessor_http_inspect");
+		} else {
+			unlink "${General::swroot}/snort/enable_preprocessor_http_inspect";
+		}
 
-}
+		system('/usr/local/bin/snortctrl restart >/dev/null');
+	}
 
-	 # INSTALLMD5 is not in the form, so not retrieved by getcgihash
+	# INSTALLMD5 is not in the form, so not retrieved by getcgihash
 	&General::readhash("${General::swroot}/snort/settings", \%snortsettings);
 
-if ($snortsettings{'ACTION'} eq $Lang::tr{'download new ruleset'} || $snortsettings{'ACTION'} eq $Lang::tr{'upload new ruleset'}) {
-
-	my @df = `/bin/df -B M /var`;
-	foreach my $line (@df) {
-		next if $line =~ m/^Filesystem/;
-		my $return;
-
-		if ($line =~ m/dev/ ) {
-		$line =~ m/^.* (\d+)M.*$/;
-		my @temp = split(/ +/,$line);
-			if ($1<300) {
-				$errormessage = "$Lang::tr{'not enough disk space'} < 300MB, /var $1MB";
-			} else {
-
-				if ( $snortsettings{'ACTION'} eq $Lang::tr{'download new ruleset'} ){
-
-					&downloadrulesfile();
-					sleep(3);
-					$return = `cat /var/tmp/log 2>/dev/null`;
-
-				} elsif ( $snortsettings{'ACTION'} eq $Lang::tr{'upload new ruleset'} ) {
-					my $upload = $a->param("UPLOAD");
-					open UPLOADFILE, ">/var/tmp/snortrules.tar.gz";
-					binmode $upload;
-					while ( <$upload> ) {
-					print UPLOADFILE;
+	if ($snortsettings{'ACTION'} eq $Lang::tr{'download new ruleset'} || $snortsettings{'ACTION'} eq $Lang::tr{'upload new ruleset'}) {
+		my @df = `/bin/df -B M /var`;
+		foreach my $line (@df) {
+			next if $line =~ m/^Filesystem/;
+			my $return;
+
+			if ($line =~ m/dev/ ) {
+				$line =~ m/^.* (\d+)M.*$/;
+				my @temp = split(/ +/,$line);
+				if ($1<300) {
+					$errormessage = "$Lang::tr{'not enough disk space'} < 300MB, /var $1MB";
+				} else {
+					if ( $snortsettings{'ACTION'} eq $Lang::tr{'download new ruleset'}) {
+						&downloadrulesfile();
+						sleep(3);
+						$return = `cat /var/tmp/log 2>/dev/null`;
+
+					} elsif ( $snortsettings{'ACTION'} eq $Lang::tr{'upload new ruleset'}) {
+						my $upload = $a->param("UPLOAD");
+						open UPLOADFILE, ">/var/tmp/snortrules.tar.gz";
+						binmode $upload;
+						while ( <$upload> ) {
+							print UPLOADFILE;
+						}
+						close UPLOADFILE;
 					}
-					close UPLOADFILE;
-				}
 
-					if ($return =~ "ERROR"){
+					if ($return =~ "ERROR") {
 						$errormessage = "<br /><pre>".$return."</pre>";
 					} else {
 						system("/usr/local/bin/oinkmaster.pl -v -s -u file:///var/tmp/snortrules.tar.gz -C /var/ipfire/snort/oinkmaster.conf -o /etc/snort/rules >>/var/tmp/log 2>&1 &");
 						sleep(2);
 					}
+				}
 			}
 		}
 	}