RHEL 6 : tigervnc (RHSA-2011:0871)

2011-06-16T00:00:00
ID REDHAT-RHSA-2011-0871.NASL
Type nessus
Reporter Tenable
Modified 2018-11-26T00:00:00

Description

Updated tigervnc packages that fix one security issue are now available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having moderate security impact. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available from the CVE link in the References section.

Virtual Network Computing (VNC) is a remote display system which allows you to view a computer's desktop environment not only on the machine where it is running, but from anywhere on the Internet and from a wide variety of machine architectures. TigerVNC is a suite of VNC servers and clients.

It was discovered that vncviewer could prompt for and send authentication credentials to a remote server without first properly validating the server's X.509 certificate. As vncviewer did not indicate that the certificate was bad or missing, a man-in-the-middle attacker could use this flaw to trick a vncviewer client into connecting to a spoofed VNC server, allowing the attacker to obtain the client's credentials. (CVE-2011-1775)

All tigervnc users should upgrade to these updated packages, which contain a backported patch to correct this issue.

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Red Hat Security Advisory RHSA-2011:0871. The text 
# itself is copyright (C) Red Hat, Inc.
#

include("compat.inc");

if (description)
{
  script_id(55160);
  script_version ("1.11");
  script_cvs_date("Date: 2018/11/26 11:02:15");

  script_cve_id("CVE-2011-1775");
  script_bugtraq_id(47738);
  script_xref(name:"RHSA", value:"2011:0871");

  script_name(english:"RHEL 6 : tigervnc (RHSA-2011:0871)");
  script_summary(english:"Checks the rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Red Hat host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Updated tigervnc packages that fix one security issue are now
available for Red Hat Enterprise Linux 6.

The Red Hat Security Response Team has rated this update as having
moderate security impact. A Common Vulnerability Scoring System (CVSS)
base score, which gives a detailed severity rating, is available from
the CVE link in the References section.

Virtual Network Computing (VNC) is a remote display system which
allows you to view a computer's desktop environment not only on the
machine where it is running, but from anywhere on the Internet and
from a wide variety of machine architectures. TigerVNC is a suite of
VNC servers and clients.

It was discovered that vncviewer could prompt for and send
authentication credentials to a remote server without first properly
validating the server's X.509 certificate. As vncviewer did not
indicate that the certificate was bad or missing, a man-in-the-middle
attacker could use this flaw to trick a vncviewer client into
connecting to a spoofed VNC server, allowing the attacker to obtain
the client's credentials. (CVE-2011-1775)

All tigervnc users should upgrade to these updated packages, which
contain a backported patch to correct this issue."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/security/cve/cve-2011-1775"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://access.redhat.com/errata/RHSA-2011:0871"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tigervnc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tigervnc-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tigervnc-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tigervnc-server-applet");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:tigervnc-server-module");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6.1");

  script_set_attribute(attribute:"patch_publication_date", value:"2011/06/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2011/06/16");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2011-2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Red Hat Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Red Hat" >!< release) audit(AUDIT_OS_NOT, "Red Hat");
os_ver = eregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Red Hat");
os_ver = os_ver[1];
if (! ereg(pattern:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 6.x", "Red Hat " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) 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$" && "s390" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);

yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
if (!empty_or_null(yum_updateinfo)) 
{
  rhsa = "RHSA-2011:0871";
  yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
  if (!empty_or_null(yum_report))
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : yum_report 
    );
    exit(0);
  }
  else
  {
    audit_message = "affected by Red Hat security advisory " + rhsa;
    audit(AUDIT_OS_NOT, audit_message);
  }
}
else
{
  flag = 0;
  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"tigervnc-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"tigervnc-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"tigervnc-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"tigervnc-debuginfo-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"tigervnc-debuginfo-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"tigervnc-debuginfo-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"tigervnc-server-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"s390x", reference:"tigervnc-server-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"tigervnc-server-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", reference:"tigervnc-server-applet-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"i686", reference:"tigervnc-server-module-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;

  if (rpm_check(release:"RHEL6", cpu:"x86_64", reference:"tigervnc-server-module-1.0.90-0.15.20110314svn4359.el6_1.1")) flag++;


  if (flag)
  {
    security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get() + redhat_report_package_caveat()
    );
    exit(0);
  }
  else
  {
    tested = pkg_tests_get();
    if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
    else audit(AUDIT_PACKAGE_NOT_INSTALLED, "tigervnc / tigervnc-debuginfo / tigervnc-server / etc");
  }
}