Debian DLA-2369-1 : libxml2 security update

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-2369-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include('compat.inc');

if (description)
{
  script_id(140469);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2024/02/21");

  script_cve_id(
    "CVE-2017-18258",
    "CVE-2017-8872",
    "CVE-2018-14404",
    "CVE-2018-14567",
    "CVE-2019-19956",
    "CVE-2019-20388",
    "CVE-2020-24977",
    "CVE-2020-7595"
  );

  script_name(english:"Debian DLA-2369-1 : libxml2 security update");

  script_set_attribute(attribute:"synopsis", value:
"The remote Debian host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"Several security vulnerabilities were corrected in libxml2, the GNOME
XML library.

CVE-2017-8872

Global buffer-overflow in the htmlParseTryOrFinish function.

CVE-2017-18258

The xz_head function in libxml2 allows remote attackers to cause a
denial of service (memory consumption) via a crafted LZMA file,
because the decoder functionality does not restrict memory usage to
what is required for a legitimate file.

CVE-2018-14404

A NULL pointer dereference vulnerability exists in the
xpath.c:xmlXPathCompOpEval() function of libxml2 when parsing an
invalid XPath expression in the XPATH_OP_AND or XPATH_OP_OR case.
Applications processing untrusted XSL format inputs may be vulnerable
to a denial of service attack.

CVE-2018-14567

If the option --with-lzma is used, allows remote attackers to cause a
denial of service (infinite loop) via a crafted XML file.

CVE-2019-19956

The xmlParseBalancedChunkMemoryRecover function has a memory leak
related to newDoc->oldNs.

CVE-2019-20388

A memory leak was found in the xmlSchemaValidateStream function of
libxml2. Applications that use this library may be vulnerable to
memory not being freed leading to a denial of service.

CVE-2020-7595

Infinite loop in xmlStringLenDecodeEntities can cause a denial of
service.

CVE-2020-24977

Out-of-bounds read restricted to xmllint --htmlout.

For Debian 9 stretch, these problems have been fixed in version
2.9.4+dfsg1-2.2+deb9u3.

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.");
  script_set_attribute(attribute:"see_also", value:"https://lists.debian.org/debian-lts-announce/2020/09/msg00009.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:N/C:P/I:N/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:POC/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:N/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-24977");
  script_set_attribute(attribute:"cvss3_score_source", value:"CVE-2017-8872");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/05/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/09/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/09/10");

  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:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Debian Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2020-2024 and is owned by Tenable, Inc. or an Affiliate thereof.");

  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+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-dev", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-doc", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-utils", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"libxml2-utils-dbg", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"python-libxml2", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"python-libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"python3-libxml2", reference:"2.9.4+dfsg1-2.2+deb9u3")) flag++;
if (deb_check(release:"9.0", prefix:"python3-libxml2-dbg", reference:"2.9.4+dfsg1-2.2+deb9u3")) 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");