Ubuntu 14.04 LTS : bash vulnerability (USN-2363-2)

2014-09-26T00:00:00
ID UBUNTU_USN-2363-2.NASL
Type nessus
Reporter Tenable
Modified 2016-08-16T00:00:00

Description

USN-2363-1 fixed a vulnerability in Bash. Due to a build issue, the patch for CVE-2014-7169 didn't get properly applied in the Ubuntu 14.04 LTS package. This update fixes the problem.

We apologize for the inconvenience.

Tavis Ormandy discovered that the security fix for Bash included in USN-2362-1 was incomplete. An attacker could use this issue to bypass certain environment restrictions. (CVE-2014-7169).

Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-2363-2. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(77898);
  script_version("$Revision: 1.16 $");
  script_cvs_date("$Date: 2016/08/16 14:42:21 $");

  script_cve_id("CVE-2014-7169");
  script_bugtraq_id(70137);
  script_osvdb_id(112004);
  script_xref(name:"USN", value:"2363-2");
  script_xref(name:"IAVA", value:"2014-A-0142");

  script_name(english:"Ubuntu 14.04 LTS : bash vulnerability (USN-2363-2)");
  script_summary(english:"Checks dpkg output for updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Ubuntu host is missing a security-related patch."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"USN-2363-1 fixed a vulnerability in Bash. Due to a build issue, the
patch for CVE-2014-7169 didn't get properly applied in the Ubuntu
14.04 LTS package. This update fixes the problem.

We apologize for the inconvenience.

Tavis Ormandy discovered that the security fix for Bash included in
USN-2362-1 was incomplete. An attacker could use this issue to bypass
certain environment restrictions. (CVE-2014-7169).

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(attribute:"solution", value:"Update the affected bash package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:ND");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'Apache mod_cgi Bash Environment Variable Code Injection (Shellshock)');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:bash");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");

  script_set_attribute(attribute:"patch_publication_date", value:"2014/09/25");
  script_set_attribute(attribute:"plugin_publication_date", value:"2014/09/26");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2014-2016 Canonical, Inc. / NASL script (C) 2014-2016 Tenable Network Security, Inc.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("misc_func.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! ereg(pattern:"^(14\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 14.04", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Ubuntu", cpu);

flag = 0;

if (ubuntu_check(osver:"14.04", pkgname:"bash", pkgver:"4.3-7ubuntu1.3")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "bash");
}