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nessusUbuntu Security Notice (C) 2005-2019 Canonical, Inc. / NASL script (C) 2006-2016 Tenable Network Security, Inc.UBUNTU_USN-179-1.NASL
HistoryJan 15, 2006 - 12:00 a.m.

Ubuntu 4.10 / 5.04 : openssl weak default configuration (USN-179-1)

2006-01-1500:00:00
Ubuntu Security Notice (C) 2005-2019 Canonical, Inc. / NASL script (C) 2006-2016 Tenable Network Security, Inc.
www.tenable.com
13

The current default algorithm for creating ‘message digests’ (electronic signatures) for certificates created by openssl is MD5.
However, this algorithm is not deemed secure any more, and some practical attacks have been demonstrated which could allow an attacker to forge certificates with a valid certification authority signature even if he does not know the secret CA signing key.

Therefore all Ubuntu versions of openssl have now been changed to use SHA-1 by default. This is a more appropriate default algorithm for the majority of use cases; however, if you still want to use MD5 as default, you can revert this change by changing the two instances of ‘default_md = sha1’ to ‘default_md = md5’ in /etc/ssl/openssl.cnf.

A detailed explanation and further links can be found at

http://www.cits.rub.de/MD5Collisions/

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.

#%NASL_MIN_LEVEL 70300

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-179-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include('deprecated_nasl_level.inc');
include('compat.inc');

if (description)
{
  script_id(20589);
  script_version("1.20");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/19");

  script_cve_id("CVE-2005-2946");
  script_xref(name:"USN", value:"179-1");

  script_name(english:"Ubuntu 4.10 / 5.04 : openssl weak default configuration (USN-179-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The current default algorithm for creating 'message digests'
(electronic signatures) for certificates created by openssl is MD5.
However, this algorithm is not deemed secure any more, and some
practical attacks have been demonstrated which could allow an attacker
to forge certificates with a valid certification authority signature
even if he does not know the secret CA signing key.

Therefore all Ubuntu versions of openssl have now been changed to use
SHA-1 by default. This is a more appropriate default algorithm for the
majority of use cases; however, if you still want to use MD5 as
default, you can revert this change by changing the two instances of
'default_md = sha1' to 'default_md = md5' in /etc/ssl/openssl.cnf.

A detailed explanation and further links can be found at

http://www.cits.rub.de/MD5Collisions/

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 libssl-dev, libssl0.9.7 and / or openssl packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No exploit is required");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(310);

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libssl-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libssl0.9.7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:openssl");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:4.10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:5.04");

  script_set_attribute(attribute:"patch_publication_date", value:"2005/09/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2006/01/15");
  script_set_attribute(attribute:"vuln_publication_date", value:"2005/09/09");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2005-2019 Canonical, Inc. / NASL script (C) 2006-2016 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:"^(4\.10|5\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 4.10 / 5.04", "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:"4.10", pkgname:"libssl-dev", pkgver:"0.9.7d-3ubuntu0.2")) flag++;
if (ubuntu_check(osver:"4.10", pkgname:"libssl0.9.7", pkgver:"0.9.7d-3ubuntu0.2")) flag++;
if (ubuntu_check(osver:"4.10", pkgname:"openssl", pkgver:"0.9.7d-3ubuntu0.2")) flag++;
if (ubuntu_check(osver:"5.04", pkgname:"libssl-dev", pkgver:"0.9.7e-3ubuntu0.1")) flag++;
if (ubuntu_check(osver:"5.04", pkgname:"libssl0.9.7", pkgver:"0.9.7e-3ubuntu0.1")) flag++;
if (ubuntu_check(osver:"5.04", pkgname:"openssl", pkgver:"0.9.7e-3ubuntu0.1")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    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, "libssl-dev / libssl0.9.7 / openssl");
}
VendorProductVersionCPE
canonicalubuntu_linuxlibssl-devp-cpe:/a:canonical:ubuntu_linux:libssl-dev
canonicalubuntu_linuxlibssl0.9.7p-cpe:/a:canonical:ubuntu_linux:libssl0.9.7
canonicalubuntu_linuxopensslp-cpe:/a:canonical:ubuntu_linux:openssl
canonicalubuntu_linux4.10cpe:/o:canonical:ubuntu_linux:4.10
canonicalubuntu_linux5.04cpe:/o:canonical:ubuntu_linux:5.04