FreeBSD : cURL library -- cert name check ignore with GnuTLS (4e1f4abc-6837-11e3-9cda-3c970e169bc2)

2013-12-19T00:00:00
ID FREEBSD_PKG_4E1F4ABC683711E39CDA3C970E169BC2.NASL
Type nessus
Reporter Tenable
Modified 2013-12-26T00:00:00

Description

cURL project reports :

libcurl is vulnerable to a case of missing out the checking of the certificate CN or SAN name field when the digital signature verification is turned off.

libcurl offers two separate and independent options for verifying a server's TLS certificate. CURLOPT_SSL_VERIFYPEER and CURLOPT_SSL_VERIFYHOST. The first one tells libcurl to verify the trust chain using a CA cert bundle, while the second tells libcurl to make sure that the name fields in the server certificate meets the criteria. Both options are enabled by default.

This flaw had the effect that when an application disabled CURLOPT_SSL_VERIFYPEER, libcurl mistakenly also skipped the CURLOPT_SSL_VERIFYHOST check. Applications can disable CURLOPT_SSL_VERIFYPEER and still achieve security by doing the check on its own using other means.

The curl command line tool is not affected by this problem as it either enables both options or disables both at the same time.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2013 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
# 
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include("compat.inc");

if (description)
{
  script_id(71530);
  script_version("$Revision: 1.2 $");
  script_cvs_date("$Date: 2013/12/26 12:38:00 $");

  script_cve_id("CVE-2013-6422");

  script_name(english:"FreeBSD : cURL library -- cert name check ignore with GnuTLS (4e1f4abc-6837-11e3-9cda-3c970e169bc2)");
  script_summary(english:"Checks for updated package in pkg_info output");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote FreeBSD host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"cURL project reports :

libcurl is vulnerable to a case of missing out the checking of the
certificate CN or SAN name field when the digital signature
verification is turned off.

libcurl offers two separate and independent options for verifying a
server's TLS certificate. CURLOPT_SSL_VERIFYPEER and
CURLOPT_SSL_VERIFYHOST. The first one tells libcurl to verify the
trust chain using a CA cert bundle, while the second tells libcurl to
make sure that the name fields in the server certificate meets the
criteria. Both options are enabled by default.

This flaw had the effect that when an application disabled
CURLOPT_SSL_VERIFYPEER, libcurl mistakenly also skipped the
CURLOPT_SSL_VERIFYHOST check. Applications can disable
CURLOPT_SSL_VERIFYPEER and still achieve security by doing the check
on its own using other means.

The curl command line tool is not affected by this problem as it
either enables both options or disables both at the same time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"http://curl.haxx.se/docs/adv_20131217.html"
  );
  # http://www.freebsd.org/ports/portaudit/4e1f4abc-6837-11e3-9cda-3c970e169bc2.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?b38ebc86"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:H/Au:N/C:P/I:P/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:curl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2013/12/17");
  script_set_attribute(attribute:"patch_publication_date", value:"2013/12/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2013/12/19");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2013 Tenable Network Security, Inc.");
  script_family(english:"FreeBSD Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("audit.inc");
include("freebsd_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"curl>=7.21.4<7.33.0_2")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:pkg_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");