Vulnerabilities > CVE-2015-8787 - NULL Pointer Dereference vulnerability in Linux Kernel

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-2890-3. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(88526);
  script_version("2.11");
  script_cvs_date("Date: 2019/09/18 12:31:45");

  script_cve_id("CVE-2013-7446", "CVE-2015-7513", "CVE-2015-7550", "CVE-2015-7990", "CVE-2015-8374", "CVE-2015-8543", "CVE-2015-8569", "CVE-2015-8575", "CVE-2015-8787");
  script_xref(name:"USN", value:"2890-3");

  script_name(english:"Ubuntu 15.10 : linux-raspi2 vulnerabilities (USN-2890-3)");
  script_summary(english:"Checks dpkg output for updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Ubuntu host is missing a security-related patch."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that a use-after-free vulnerability existed in the
AF_UNIX implementation in the Linux kernel. A local attacker could use
crafted epoll_ctl calls to cause a denial of service (system crash) or
expose sensitive information. (CVE-2013-7446)

It was discovered that the KVM implementation in the Linux kernel did
not properly restore the values of the Programmable Interrupt Timer
(PIT). A user-assisted attacker in a KVM guest could cause a denial of
service in the host (system crash). (CVE-2015-7513)

It was discovered that the Linux kernel keyring subsystem contained a
race between read and revoke operations. A local attacker could use
this to cause a denial of service (system crash). (CVE-2015-7550)

Sasha Levin discovered that the Reliable Datagram Sockets (RDS)
implementation in the Linux kernel had a race condition when checking
whether a socket was bound or not. A local attacker could use this to
cause a denial of service (system crash). (CVE-2015-7990)

It was discovered that the Btrfs implementation in the Linux kernel
incorrectly handled compressed inline extants on truncation. A local
attacker could use this to expose sensitive information.
(CVE-2015-8374)

Guoyong Gang discovered that the Linux kernel networking
implementation did not validate protocol identifiers for certain
protocol families, A local attacker could use this to cause a denial
of service (system crash) or possibly gain administrative privileges.
(CVE-2015-8543)

Dmitry Vyukov discovered that the pptp implementation in the Linux
kernel did not verify an address length when setting up a socket. A
local attacker could use this to craft an application that exposed
sensitive information from kernel memory. (CVE-2015-8569)

David Miller discovered that the Bluetooth implementation in the Linux
kernel did not properly validate the socket address length for
Synchronous Connection-Oriented (SCO) sockets. A local attacker could
use this to expose sensitive information. (CVE-2015-8575)

It was discovered that the netfilter Network Address Translation (NAT)
implementation did not ensure that data structures were initialized
when handling IPv4 addresses. An attacker could use this to cause a
denial of service (system crash). (CVE-2015-8787).

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu 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://usn.ubuntu.com/2890-3/"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected linux-image-4.2-raspi2 package."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:C/I:C/A:C");
  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: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:canonical:ubuntu_linux:linux-image-4.2-raspi2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:15.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2015/12/28");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/02/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/02/02");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2016-2019 Canonical, Inc. / NASL script (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl", "linux_alt_patch_detect.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("ksplice.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(15\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 15.10", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) 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, "Ubuntu", cpu);

if (get_one_kb_item("Host/ksplice/kernel-cves"))
{
  rm_kb_item(name:"Host/uptrack-uname-r");
  cve_list = make_list("CVE-2013-7446", "CVE-2015-7513", "CVE-2015-7550", "CVE-2015-7990", "CVE-2015-8374", "CVE-2015-8543", "CVE-2015-8569", "CVE-2015-8575", "CVE-2015-8787");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for USN-2890-3");
  }
  else
  {
    _ubuntu_report = ksplice_reporting_text();
  }
}

flag = 0;

if (ubuntu_check(osver:"15.10", pkgname:"linux-image-4.2.0-1022-raspi2", pkgver:"4.2.0-1022.29")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "linux-image-4.2-raspi2");
}