Debian DLA-1500-2 : openssh regression update

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-1500-2. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

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

if (description)
{
  script_id(117432);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/11");

  script_name(english:"Debian DLA-1500-2 : openssh regression update");
  script_summary(english:"Checks dpkg output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The security update of OpenSSH announced as DLA 1500-1 introduced a
bug in openssh-client: when X11 forwarding is enabled (via system-wide
configuration in ssh_config or via -X command line switch), but no
DISPLAY is set, the client produces a 'DISPLAY '(null)' invalid;
disabling X11 forwarding' warning. These bug was introduced by the
patch set to fix the CVE-2016-1908 issue. For reference, the following
is the relevant section of the original announcement :

CVE-2016-1908

OpenSSH mishandled untrusted X11 forwarding when the X server disables
the SECURITY extension. Untrusted connections could obtain trusted X11
forwarding privileges. Reported by Thomas Hoger.

For Debian 8 'Jessie', this problem has been fixed in version
1:6.7p1-5+deb8u7.

We recommend that you upgrade your openssh packages.

NOTE: Tenable Network Security has extracted the preceding description
block directly from the DLA security advisory. Tenable has attempted
to automatically clean and format it as much as possible without
introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://lists.debian.org/debian-lts-announce/2018/09/msg00014.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/openssh"
  );
  script_set_attribute(attribute:"solution", value:"Upgrade the affected packages.");
  script_set_attribute(attribute:"risk_factor", value:"High");
  script_set_cvss_temporal_vector("CVSS2#E:ND/RL:OF/RC:C");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-client");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-client-udeb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-server-udeb");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:openssh-sftp-server");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ssh");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ssh-askpass-gnome");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:ssh-krb5");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"patch_publication_date", value:"2018/09/12");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/09/12");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2021 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Debian Local Security Checks");

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

  exit(0);
}


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


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"8.0", prefix:"openssh-client", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"openssh-client-udeb", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"openssh-server", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"openssh-server-udeb", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"openssh-sftp-server", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"ssh", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"ssh-askpass-gnome", reference:"1:6.7p1-5+deb8u7")) flag++;
if (deb_check(release:"8.0", prefix:"ssh-krb5", reference:"1:6.7p1-5+deb8u7")) flag++;

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