Fedora 26 : glibc (2018-8e27ad96ed)

#%NASL_MIN_LEVEL 70300
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Fedora Security Advisory FEDORA-2018-8e27ad96ed.
#

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

if (description)
{
  script_id(106281);
  script_version("3.7");
  script_set_attribute(attribute:"plugin_modification_date", value:"2021/01/06");

  script_cve_id("CVE-2017-15670", "CVE-2017-15671", "CVE-2017-15804", "CVE-2017-16997", "CVE-2018-1000001");
  script_xref(name:"FEDORA", value:"2018-8e27ad96ed");

  script_name(english:"Fedora 26 : glibc (2018-8e27ad96ed)");
  script_summary(english:"Checks rpm output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"This update addresses two security vulnerabilities :

  - CVE-2017-15670, CVE-2017-15671, CVE-2017-15804: Various
    vulnerabilities could lead to memory corruption in the
    `glob` and `glob64` function. (RHBZ#1505298,
    RHBZ##1504807)

  - CVE-2017-16997: Check for empty tokens before dynamic
    string token expansion in the dynamic linker, so that
    pre-existing privileged programs with `$ORIGIN`
    rpaths/runpaths do not cause the dynamic linker to
    search the current directory, potentially leading to
    privilege escalation. (RHBZ#1526866).

  - CVE-2018-1000001: `getcwd` would sometimes return a
    non-absolute path, confusing the `realpath` function,
    leading to privilege escalation in conjunction with user
    namespaces. (RHBZ#1533837) 

In addition, this update replaces the dynamic linker trampoline on
x86-64 with a version which uses the `XSAVE` instruction if it is
available. This improves compatibility with future hardware and
compilers which do not follow the x86-64 ABI. This update also adjusts
the thread stack size accounting to provide additional stack space
compared to previous glibc versions (to avoid introducing
RHBZ#1527887).

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
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://bodhi.fedoraproject.org/updates/FEDORA-2018-8e27ad96ed"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected glibc package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:F/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:F/RL:O/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");
  script_set_attribute(attribute:"metasploit_name", value:'glibc "realpath()" Privilege Escalation');
  script_set_attribute(attribute:"exploit_framework_metasploit", value:"true");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:glibc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:26");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/10/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/01/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/24");
  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:"Fedora Local Security Checks");

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

  exit(0);
}


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


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/RedHat/release");
if (isnull(release) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^26([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 26", "Fedora " + os_ver);

if (!get_kb_item("Host/RedHat/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);


flag = 0;
if (rpm_check(release:"FC26", reference:"glibc-2.25-13.fc26")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "glibc");
}