Debian DLA-742-1 : chrony 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-742-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

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

if (description)
{
  script_id(95775);
  script_version("3.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/11");

  script_cve_id("CVE-2016-1567");

  script_name(english:"Debian DLA-742-1 : chrony security update");
  script_summary(english:"Checks dpkg output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that Chrony, a versatile implementation of the
Network Time Protocol, did not verify peer associations of symmetric
keys when authenticating packets, which might allow remote attackers
to conduct impersonation attacks via an arbitrary trusted key, aka a
'skeleton key.'

This update also resolves Debian bug #568492.

For Debian 7 'Wheezy', these problems have been fixed in version
1.24-3.1+deb7u4.

We recommend that you upgrade your chrony 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/2016/12/msg00017.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/wheezy/chrony"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Upgrade the affected chrony package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/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:H/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:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:chrony");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:7.0");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/12/13");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/12/14");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2021 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:"7.0", prefix:"chrony", reference:"1.24-3.1+deb7u4")) flag++;

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