GLSA-201603-04 : FUSE: incorrect filtering of environment variables leading to privilege escalation

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 201603-04.
#
# The advisory text is Copyright (C) 2001-2016 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

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

if (description)
{
  script_id(89810);
  script_version("2.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/11");

  script_cve_id("CVE-2015-3202");
  script_xref(name:"GLSA", value:"201603-04");

  script_name(english:"GLSA-201603-04 : FUSE: incorrect filtering of environment variables leading to privilege escalation");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The remote host is affected by the vulnerability described in GLSA-201603-04
(FUSE: incorrect filtering of environment variables leading to privilege escalation)

    The fusermount binary calls setuid(geteuid()) to reset the RUID when it
      invokes /bin/mount so that it can use privileged mount options that are
      normally restricted if RUID != EUID.  FUSE does not properly clear
      environment variables before invoking mount or umount as root allowing
      this to be passed to operations using elevated privileges such as
      LIBMOUNT_MTAB that is used by the mount commands debugging feature.
  
Impact :

    The FUSE vulnerability allows a local, unprivileged user to overwrite
      arbitrary files on the system.
  
Workaround :

    There is no known work around at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/201603-04"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All FUSE users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=sys-fs/fuse-2.9.4'"
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:F/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"exploit_framework_core", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:fuse");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2016/03/09");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/03/10");
  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:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"sys-fs/fuse", unaffected:make_list("ge 2.9.4"), vulnerable:make_list("lt 2.9.4"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_note(port:0, extra:qpkg_report_get());
  else security_note(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "FUSE");
}