openVAS scan against new instance fails test (possible false positive) How to debug plug-in

Question

I have openVAS installed from the atomic corp YUM repo, and it all seems to be functioning wonderfully, however I am seeing a single "Security Hole" which is that OpenVAS detects that "arora" is installed on the system, (which it is not)

I am getting a positive result for "Arora Common Name SSL Certificate Spoofing Vulnerability (Linux)" which is documented here;

I pulled up the script, and it seems to be searching the binary with file name "arora"; (

modName = find_file(file_name:"arora", file_path:"/usr/bin/",
                      useregex:TRUE, regexpar:"$", sock:sock);

However the target in question does not have any binaries installed called arora, nor even any documents with files, or even sub strings "arora" in a case insensitive search;

[root@52-56-149-11 ~]# locate Arora
[root@52-56-149-11 ~]# locate rora
[root@52-56-149-11 ~]# locate arora
[root@52-56-149-11 ~]# find / | grep -i arora

all return nothing.

Can I run this test by hand, and inspect the values or something?

(I am new to openvas nasl scripts, so any points to documentation would be helpful, I did look at the troubleshooting guide in the 1.0.1 compendium, but I could not work out how to send the SSH Credentials as parameters to the nasl script)

Full source of my installed copy of the test is as follows;

###############################################################################
# Openvas Vulnerability Test
# $id: secpod_arora_cn_ssl_cert_spoofing_vuln_lin.nasl 2011-12-15 14:01:47z dec $
#
# Arora Common Name SSL Certificate Spoofing Vulnerability (Linux)
#
# Authors:
# Madhuri D<dmadhuri@secpod.com  <mailto:dmadhuri@secpod.com>>
#
# Copyright:
# Copyright (c) 2011 SecPod,http://www.secpod.com  <http://www.secpod.com/>
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the gnu general public license version 2
# (or any later version), as published by the free software foundation.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
###############################################################################

if(description)
{
  script_id(902764);
  script_version("$Revision$");
  script_cve_id("CVE-2011-3367");
  script_bugtraq_id(49925);
  script_tag(name:"cvss_base", value:"5.0");
  script_tag(name:"cvss_base_vector", value:"AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_tag(name:"risk_factor", value:"Medium");
  script_tag(name:"last_modification", value:"$Date$");
  script_tag(name:"creation_date", value:"2011-12-15 14:01:47 +0530 (Thu, 15 Dec 2011)");
  script_name("Arora Common Name SSL Certificate Spoofing Vulnerability (Linux)");
  desc = "
  Overview: This host is installed with Arora and is prone common name SSL
  certificate spoofing vulnerability.

  Vulnerability Insight:
  The flaw is caused due to not using a certain font when rendering certificate
  fields in a security dialog.

  Impact:
  Successful exploitation will allow remote attackers to spoof the common name
  (CN) of a certificate via rich text.

  Impact Level: Application.

  Affected Software :
  Arora version 0.11 and prior

  Fix: No solution or patch is available as on 15th December 2011. Information
  regarding this issue will be updated once the solution details are available
  For updates refer,http://code.google.com/p/arora/downloads/list

  References:
  http://secunia.com/advisories/46269
  http://www.securityfocus.com/archive/1/520041
  https://bugzilla.redhat.com/show_bug.cgi?id=746875
  http://archives.neohapsis.com/archives/fulldisclosure/2011-10/att-0353/NDSA20111003.txt.asc  ";

  script_description(desc);
  script_summary("Check for the version of Arora");
  script_category(ACT_GATHER_INFO);
  script_copyright("Copyright (C) 2011 SecPod");
  script_family("General");
  script_dependencies("find_service.nes");
  script_mandatory_keys("login/SSH/success");
  exit(0);
}


include("ssh_func.inc");
include("version_func.inc");

## Open SSH Login connection
sock = ssh_login_or_reuse_connection();
if(!sock){
  exit(0);
}

## Confirm Linux, as SSH can be instslled on Windows as well
result = ssh_cmd(socket:sock, cmd:"uname");
if("Linux">!<  result){
  exit(0);
}

grep = find_bin(prog_name:"grep", sock:sock);
grep = chomp(grep[0]);

garg[0] = "-o";
garg[1] = "-m1";
garg[2] = "-a";
garg[3] = string("[0]\\.[0-9][0-9]\\.[0-9]");

## Getting arora file path
modName = find_file(file_name:"arora", file_path:"/usr/bin/",
                      useregex:TRUE, regexpar:"$", sock:sock);
foreach binaryName (modName)
{
  binaryName = chomp(binaryName);
  arg = garg[0] + " " + garg[1] + " " + garg[2] + " " + raw_string(0x22) +
          garg[3] + raw_string(0x22) + " " + binaryName;
}

## Grep the version
arrVer = get_bin_version(full_prog_name:grep, version_argv:arg,
                              ver_pattern:"([0-9.]+)", sock:sock);
if(arrVer)
{
  ## Check the arora version
  if(version_is_less_equal(version:arrVer[0], test_version:"0.11.0")){
      security_warning(0);
  }
}

ssh_close_connection();


  [1]: http://wald.intevation.org/scm/viewvc.php/trunk/openvas-plugins/scripts/secpod_arora_cn_ssl_cert_spoofing_vuln_lin.nasl?root=openvas&view=markup

Turns out this was a bug, which has been fixed. But I am still interested in debugging techniques. — Tom, Feb 07 '12 at 20:47

Cheekysoft · Accepted Answer · 2012-02-08T16:05:36.583

Most NASL scripts are simple enough to debug using "print" statements. Use the NASL function display( var ) to show the content of a varialbe on screen.

Then just run the script against the target

nasl -s -t ipaddress myscript.nasl

Bear in mind that this won't run the dependencies. If the effect of the dependencies are necessary for your test, you can specify your own knowledge-base file with the -k kbfile option.

If you want a full trace of every function call, request and response; then also add the -a switch. This can be very useful, but produces a lot of output.

Familiarise yourself with the manual. It's mostly reliable, but don't expect everything in it to be factually accurate, complete or exhibit self-referential integrity :-)

openVAS scan against new instance fails test (possible false positive) How to debug plug-in

1 Answers1