An issue was discovered in the size of the stack guard page on Linux, specifically a 4k stack guard page is not sufficiently large and can be jmp’ed over, this affects Linux Kernel versions 4.11.5 and earlier (the stackguard page was introduced in 2010). (CVE-2017-1000364)
The offset2lib patch as used by the Linux Kernel contains a vulnerability, if RLIMIT_STACK is set to RLIMIT_INFINITY and 1 Gigabyte of memory is allocated (the maximum under the 1/4 restriction) then the stack will be grown down to 0x80000000, and as the PIE binary is mapped above 0x80000000 the minimum distance between the end of the PIE binary’s read-write segment and the start of the stack becomes small enough that the stack guard page can be jumped over by an attacker. This is a different issue than CVE-2017-1000370 and CVE-2017-1000365 . (CVE-2017-1000371)
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2017-845.
#
include("compat.inc");
if (description)
{
script_id(100874);
script_version("3.9");
script_cvs_date("Date: 2019/04/10 16:10:16");
script_cve_id("CVE-2017-1000364", "CVE-2017-1000371");
script_xref(name:"ALAS", value:"2017-845");
script_name(english:"Amazon Linux AMI : kernel (ALAS-2017-845) (Stack Clash)");
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:
"An issue was discovered in the size of the stack guard page on Linux,
specifically a 4k stack guard page is not sufficiently large and can
be jmp'ed over, this affects Linux Kernel versions 4.11.5 and earlier
(the stackguard page was introduced in 2010). (CVE-2017-1000364)
The offset2lib patch as used by the Linux Kernel contains a
vulnerability, if RLIMIT_STACK is set to RLIMIT_INFINITY and 1
Gigabyte of memory is allocated (the maximum under the 1/4
restriction) then the stack will be grown down to 0x80000000, and as
the PIE binary is mapped above 0x80000000 the minimum distance between
the end of the PIE binary's read-write segment and the start of the
stack becomes small enough that the stack guard page can be jumped
over by an attacker. This is a different issue than CVE-2017-1000370
and CVE-2017-1000365 . (CVE-2017-1000371)"
);
script_set_attribute(
attribute:"see_also",
value:"https://alas.aws.amazon.com/ALAS-2017-845.html"
);
script_set_attribute(
attribute:"solution",
value:"Run 'yum update kernel' to update your system."
);
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:F/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: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:'rsh_stack_clash_priv_esc.rb');
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: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:"2017/06/19");
script_set_attribute(attribute:"in_the_news", value:"true");
script_set_attribute(attribute:"plugin_publication_date", value:"2017/06/20");
script_end_attributes();
script_category(ACT_GATHER_INFO);
script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
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-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-debuginfo-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", cpu:"i686", reference:"kernel-debuginfo-common-i686-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", cpu:"x86_64", reference:"kernel-debuginfo-common-x86_64-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-devel-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-doc-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-headers-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-debuginfo-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"kernel-tools-devel-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"perf-4.9.27-14.33.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"perf-debuginfo-4.9.27-14.33.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");
}
Vendor | Product | Version | CPE |
---|---|---|---|
amazon | linux | kernel | p-cpe:/a:amazon:linux:kernel |
amazon | linux | kernel-debuginfo | p-cpe:/a:amazon:linux:kernel-debuginfo |
amazon | linux | kernel-debuginfo-common-i686 | p-cpe:/a:amazon:linux:kernel-debuginfo-common-i686 |
amazon | linux | kernel-debuginfo-common-x86_64 | p-cpe:/a:amazon:linux:kernel-debuginfo-common-x86_64 |
amazon | linux | kernel-devel | p-cpe:/a:amazon:linux:kernel-devel |
amazon | linux | kernel-doc | p-cpe:/a:amazon:linux:kernel-doc |
amazon | linux | kernel-headers | p-cpe:/a:amazon:linux:kernel-headers |
amazon | linux | kernel-tools | p-cpe:/a:amazon:linux:kernel-tools |
amazon | linux | kernel-tools-debuginfo | p-cpe:/a:amazon:linux:kernel-tools-debuginfo |
amazon | linux | kernel-tools-devel | p-cpe:/a:amazon:linux:kernel-tools-devel |