GLSA-200611-06 : OpenSSH: Multiple Denial of Service vulnerabilities

2006-11-20T00:00:00
ID GENTOO_GLSA-200611-06.NASL
Type nessus
Reporter Tenable
Modified 2015-04-13T00:00:00

Description

The remote host is affected by the vulnerability described in GLSA-200611-06 (OpenSSH: Multiple Denial of Service vulnerabilities)

Tavis Ormandy of the Google Security Team has discovered a     pre-authentication vulnerability, causing sshd to spin until the login     grace time has been expired. Mark Dowd found an unsafe signal handler     that was vulnerable to a race condition. It has also been discovered     that when GSSAPI authentication is enabled, GSSAPI will in certain     cases incorrectly abort.

Impact :

The pre-authentication and signal handler vulnerabilities can cause a     Denial of Service in OpenSSH. The vulnerability in the GSSAPI     authentication abort could be used to determine the validity of     usernames on some platforms.

Workaround :

There is no known workaround at this time.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 200611-06.
#
# The advisory text is Copyright (C) 2001-2015 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include("compat.inc");

if (description)
{
  script_id(23671);
  script_version("$Revision: 1.14 $");
  script_cvs_date("$Date: 2015/04/13 13:56:52 $");

  script_cve_id("CVE-2006-5051", "CVE-2006-5052");
  script_bugtraq_id(20241, 20245);
  script_osvdb_id(29264, 29266);
  script_xref(name:"GLSA", value:"200611-06");

  script_name(english:"GLSA-200611-06 : OpenSSH: Multiple Denial of Service vulnerabilities");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The remote host is affected by the vulnerability described in GLSA-200611-06
(OpenSSH: Multiple Denial of Service vulnerabilities)

    Tavis Ormandy of the Google Security Team has discovered a
    pre-authentication vulnerability, causing sshd to spin until the login
    grace time has been expired. Mark Dowd found an unsafe signal handler
    that was vulnerable to a race condition. It has also been discovered
    that when GSSAPI authentication is enabled, GSSAPI will in certain
    cases incorrectly abort.
  
Impact :

    The pre-authentication and signal handler vulnerabilities can cause a
    Denial of Service in OpenSSH. The vulnerability in the GSSAPI
    authentication abort could be used to determine the validity of
    usernames on some platforms.
  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.openssh.com/txt/release-4.4"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/200611-06"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All OpenSSH users should upgrade to the latest version:
    # emerge --sync
    # emerge --ask --oneshot --verbose '>=net-misc/openssh-4.4_p1-r5'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:ND/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");
  script_cwe_id(362);

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:openssh");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2006/11/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2006/11/20");
  script_set_attribute(attribute:"vuln_publication_date", value:"2006/09/28");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2006-2015 Tenable Network Security, Inc.");
  script_family(english:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"net-misc/openssh", unaffected:make_list("ge 4.4_p1-r5"), vulnerable:make_list("lt 4.4_p1-r5"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:qpkg_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "OpenSSH");
}