Vulnerabilities > CVE-2019-18198 - Missing Release of Resource after Effective Lifetime vulnerability in multiple products

047910
CVSS 7.8 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
local
low complexity
linux
canonical
CWE-772
nessus
NVD
Published: 2019-10-18
Updated: 2023-01-20

Summary

In the Linux kernel before 5.3.4, a reference count usage error in the fib6_rule_suppress() function in the fib6 suppression feature of net/ipv6/fib6_rules.c, when handling the FIB_LOOKUP_NOREF flag, can be exploited by a local attacker to corrupt memory, aka CID-ca7a03c41753.

Vulnerable Configurations

Part Description Count
OS
Linux
5
OS
Canonical
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • HTTP DoS
    An attacker performs flooding at the HTTP level to bring down only a particular web application rather than anything listening on a TCP/IP connection. This denial of service attack requires substantially fewer packets to be sent which makes DoS harder to detect. This is an equivalent of SYN flood in HTTP. The idea is to keep the HTTP session alive indefinitely and then repeat that hundreds of times. This attack targets resource depletion weaknesses in web server software. The web server will wait to attacker's responses on the initiated HTTP sessions while the connection threads are being exhausted.

Nessus

NASL familyUbuntu Local Security Checks
NASL idUBUNTU_USN-4161-1.NASL
descriptionIt was discovered that the IPv6 routing implementation in the Linux kernel contained a reference counting error leading to a use-after-free vulnerability. A local attacker could use this to cause a denial of service (system crash) or possibly execute arbitrary code. 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.
last seen2020-06-01
modified2020-06-02
plugin id130150
published2019-10-22
reporterUbuntu Security Notice (C) 2019 Canonical, Inc. / NASL script (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/130150
titleUbuntu 19.10 : linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-raspi2 (USN-4161-1)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4161-1. 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(130150);
  script_version("1.3");
  script_cvs_date("Date: 2019/12/18");

  script_cve_id("CVE-2019-18198");
  script_xref(name:"USN", value:"4161-1");

  script_name(english:"Ubuntu 19.10 : linux, linux-aws, linux-azure, linux-gcp, linux-kvm, linux-raspi2 (USN-4161-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that the IPv6 routing implementation in the Linux
kernel contained a reference counting error leading to a
use-after-free vulnerability. A local attacker could use this to cause
a denial of service (system crash) or possibly execute arbitrary code.

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/4161-1/"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:L/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:L/AC:L/PR:L/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:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-aws");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-azure");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-gcp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-5.3-snapdragon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-aws");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-azure");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-gcp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-generic");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-generic-lpae");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-gke");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-kvm");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-lowlatency");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-raspi2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-snapdragon");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:linux-image-virtual");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/10/18");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/10/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/10/22");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2019 Canonical, Inc. / NASL script (C) 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:"^(19\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 19.10", "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-2019-18198");
  if (ksplice_cves_check(cve_list))
  {
    audit(AUDIT_PATCH_INSTALLED, "KSplice hotfix for USN-4161-1");
  }
  else
  {
    _ubuntu_report = ksplice_reporting_text();
  }
}

flag = 0;

if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-1004-aws", pkgver:"5.3.0-1004.4")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-1004-azure", pkgver:"5.3.0-1004.4")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-1004-kvm", pkgver:"5.3.0-1004.4")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-1005-gcp", pkgver:"5.3.0-1005.5")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-1008-raspi2", pkgver:"5.3.0-1008.9")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-19-generic", pkgver:"5.3.0-19.20")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-19-generic-lpae", pkgver:"5.3.0-19.20")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-19-lowlatency", pkgver:"5.3.0-19.20")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-5.3.0-19-snapdragon", pkgver:"5.3.0-19.20")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-aws", pkgver:"5.3.0.1004.5")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-azure", pkgver:"5.3.0.1004.21")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-gcp", pkgver:"5.3.0.1005.5")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-generic", pkgver:"5.3.0.19.22")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-generic-lpae", pkgver:"5.3.0.19.22")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-gke", pkgver:"5.3.0.1005.5")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-kvm", pkgver:"5.3.0.1004.4")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-lowlatency", pkgver:"5.3.0.19.22")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-raspi2", pkgver:"5.3.0.1008.4")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-snapdragon", pkgver:"5.3.0.19.22")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"linux-image-virtual", pkgver:"5.3.0.19.22")) 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-5.3-aws / linux-image-5.3-azure / linux-image-5.3-gcp / etc");
}

References