Amazon Linux AMI : kernel (ALAS-2015-523)

#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2015-523.
#

include("compat.inc");

if (description)
{
  script_id(83493);
  script_version("2.3");
  script_cvs_date("Date: 2018/04/18 15:09:35");

  script_cve_id("CVE-2015-3331", "CVE-2015-3636");
  script_xref(name:"ALAS", value:"2015-523");

  script_name(english:"Amazon Linux AMI : kernel (ALAS-2015-523)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Amazon Linux AMI host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"A buffer overflow flaw was found in the way the Linux kernel's Intel
AES-NI instructions optimized version of the RFC4106 GCM mode
decryption functionality handled fragmented packets. A remote attacker
could use this flaw to crash, or potentially escalate their privileges
on, a system over a connection with an active AEC-GCM mode IPSec
security association. (CVE-2015-3331)

It was found that the Linux kernel's ping socket implementation did
not properly handle socket unhashing during spurious disconnects,
which could lead to a use-after-free flaw. On x86-64 architecture
systems, a local user able to create ping sockets could use this flaw
to crash the system. On non-x86-64 architecture systems, a local user
able to create ping sockets could use this flaw to escalate their
privileges on the system. (CVE-2015-3636)"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/ALAS-2015-523.html"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Run 'yum clean all' followed by 'yum update kernel' to update your
system. You will need to reboot your system in order for the new
kernel to be running."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-i686");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-headers");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:kernel-tools-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:perf-debuginfo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2015/05/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2015/05/18");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2015-2018 Tenable Network Security, Inc.");
  script_family(english:"Amazon Linux Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/AmazonLinux/release", "Host/AmazonLinux/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/AmazonLinux/release");
if (isnull(release) || !strlen(release)) audit(AUDIT_OS_NOT, "Amazon Linux");
os_ver = pregmatch(pattern: "^AL(A|\d)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Amazon Linux");
os_ver = os_ver[1];
if (os_ver != "A")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux AMI", "Amazon Linux " + os_ver);
}

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


flag = 0;
if (rpm_check(release:"ALA", reference:"kernel-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-debuginfo-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", cpu:"i686", reference:"kernel-debuginfo-common-i686-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-devel-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-doc-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-headers-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-debuginfo-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-devel-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"perf-3.14.42-31.38.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"perf-debuginfo-3.14.42-31.38.amzn1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
  else security_hole(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "kernel / kernel-debuginfo / kernel-debuginfo-common-i686 / etc");
}