Debian DLA-2669-1 : libxml2 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-2669-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

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

if (description)
{
  script_id(150111);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/07/14");

  script_cve_id("CVE-2021-3541");

  script_name(english:"Debian DLA-2669-1 : libxml2 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:
"An issue has been found in libxml2, the GNOME XML library. This issue
is called 'Parameter Laughs'-attack and is related to parameter
entities expansion. It is similar to the 'Billion Laughs'-attacks
found earlier in libexpat. More information can be found at [1]

[1]
https://blog.hartwork.org/posts/cve-2021-3541-parameter-laughs-fixed-i
n-libxml2-2-9-11/

For Debian 9 stretch, this problem has been fixed in version
2.9.4+dfsg1-2.2+deb9u5.

We recommend that you upgrade your libxml2 packages.

For the detailed security status of libxml2 please refer to its
security tracker page at:
https://security-tracker.debian.org/tracker/libxml2

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."
  );
  # https://blog.hartwork.org/posts/cve-2021-3541-parameter-laughs-fixed-in-libxml2-2-9-11/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?61bdfec1"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://lists.debian.org/debian-lts-announce/2021/05/msg00024.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/stretch/libxml2"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security-tracker.debian.org/tracker/source-package/libxml2"
  );
  script_set_attribute(attribute:"solution", value:"Upgrade the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:N/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:L/UI:N/S:U/C:N/I:N/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-2021-3541");
  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:libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libxml2-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libxml2-dev");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libxml2-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libxml2-utils");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:libxml2-utils-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-libxml2-dbg");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3-libxml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3-libxml2-dbg");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:9.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2021/07/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/05/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/06/01");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 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:"9.0", prefix:"libxml2", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-dev", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-doc", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-utils", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-utils-dbg", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"python-libxml2", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"python-libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"python3-libxml2", reference:"2.9.4+dfsg1-2.2+deb9u5")) flag++;
if (deb_check(release:"9.0", prefix:"python3-libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u5")) 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");