Debian DLA-1617-1 : libvncserver security 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-1617-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

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

if (description)
{
  script_id(119877);
  script_version("1.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/11");

  script_cve_id("CVE-2018-15127", "CVE-2018-20019", "CVE-2018-20020", "CVE-2018-20021", "CVE-2018-20022", "CVE-2018-20023", "CVE-2018-20024", "CVE-2018-6307");

  script_name(english:"Debian DLA-1617-1 : libvncserver security 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:
"Kaspersky Lab discovered several vulnerabilities in libvncserver, a C
library to implement VNC server/client functionalities.

CVE-2018-6307

a heap use-after-free vulnerability in the server code of the file
transfer extension, which can result in remote code execution. This
attack appears to be exploitable via network connectivity.

CVE-2018-15127

contains a heap out-of-bound write vulnerability in the server code of
the file transfer extension, which can result in remote code
execution. This attack appears to be exploitable via network
connectivity.

CVE-2018-20019

multiple heap out-of-bound write vulnerabilities in VNC client code,
which can result in remote code execution.

CVE-2018-20020

heap out-of-bound write vulnerability in a structure in VNC client
code, which can result in remote code execution.

CVE-2018-20021

CWE-835: Infinite Loop vulnerability in VNC client code. The
vulnerability could allow an attacker to consume an excessive amount
of resources, such as CPU and RAM.

CVE-2018-20022

CWE-665: Improper Initialization weaknesses in VNC client code, which
could allow an attacker to read stack memory and can be abused for
information disclosure. Combined with another vulnerability, it can be
used to leak stack memory layout and bypass ASLR.

CVE-2018-20023

Improper Initialization vulnerability in VNC Repeater client code,
which could allow an attacker to read stack memory and can be abused
for information disclosure. Combined with another vulnerability, it
can be used to leak stack memory layout and bypass ASLR.

CVE-2018-20024

a NULL pointer dereference in VNC client code, which can result in
DoS.

For Debian 8 'Jessie', these problems have been fixed in version
0.9.9+dfsg2-6.1+deb8u4.

We recommend that you upgrade your libvncserver 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/2018/12/msg00017.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/libvncserver"
  );
  script_set_attribute(attribute:"solution", value:"Upgrade the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-20020");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncclient0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncclient0-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncserver-config");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncserver-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncserver0");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libvncserver0-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:linuxvnc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/12/19");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/12/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/12/27");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  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:"libvncclient0", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libvncclient0-dbg", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libvncserver-config", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libvncserver-dev", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libvncserver0", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"libvncserver0-dbg", reference:"0.9.9+dfsg2-6.1+deb8u4")) flag++;
if (deb_check(release:"8.0", prefix:"linuxvnc", reference:"0.9.9+dfsg2-6.1+deb8u4")) 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");