Use-after-free in receive_msg function via vectors involving BDAT commands
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to execute arbitrary code or cause a denial of service (use-after-free) via vectors involving BDAT commands. (CVE-2017-16943)
Infinite loop and stack exhaustion in receive_msg function via vectors involving BDAT commands
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88 and 4.89 allows remote attackers to cause a denial of service (infinite loop and stack exhaustion) via vectors involving BDAT commands and an improper check for a ‘.’ character signifying the end of the content, related to the bdat_getc function. (CVE-2017-16944)
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2017-932.
#
include("compat.inc");
if (description)
{
script_id(105417);
script_version("3.4");
script_cvs_date("Date: 2019/04/10 16:10:16");
script_cve_id("CVE-2017-16943", "CVE-2017-16944");
script_xref(name:"ALAS", value:"2017-932");
script_name(english:"Amazon Linux AMI : exim (ALAS-2017-932)");
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:
"Use-after-free in receive_msg function via vectors involving BDAT
commands
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88
and 4.89 allows remote attackers to execute arbitrary code or cause a
denial of service (use-after-free) via vectors involving BDAT
commands. (CVE-2017-16943)
Infinite loop and stack exhaustion in receive_msg function via vectors
involving BDAT commands
The receive_msg function in receive.c in the SMTP daemon in Exim 4.88
and 4.89 allows remote attackers to cause a denial of service
(infinite loop and stack exhaustion) via vectors involving BDAT
commands and an improper check for a '.' character signifying the end
of the content, related to the bdat_getc function. (CVE-2017-16944)"
);
script_set_attribute(
attribute:"see_also",
value:"https://alas.aws.amazon.com/ALAS-2017-932.html"
);
script_set_attribute(
attribute:"solution",
value:"Run 'yum update exim' to update your system."
);
script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim-debuginfo");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim-greylist");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim-mon");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim-mysql");
script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:exim-pgsql");
script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");
script_set_attribute(attribute:"patch_publication_date", value:"2017/12/20");
script_set_attribute(attribute:"plugin_publication_date", value:"2017/12/26");
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:"exim-4.89-4.17.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"exim-debuginfo-4.89-4.17.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"exim-greylist-4.89-4.17.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"exim-mon-4.89-4.17.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"exim-mysql-4.89-4.17.amzn1")) flag++;
if (rpm_check(release:"ALA", reference:"exim-pgsql-4.89-4.17.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, "exim / exim-debuginfo / exim-greylist / exim-mon / exim-mysql / etc");
}
Vendor | Product | Version | CPE |
---|---|---|---|
amazon | linux | exim | p-cpe:/a:amazon:linux:exim |
amazon | linux | exim-debuginfo | p-cpe:/a:amazon:linux:exim-debuginfo |
amazon | linux | exim-greylist | p-cpe:/a:amazon:linux:exim-greylist |
amazon | linux | exim-mon | p-cpe:/a:amazon:linux:exim-mon |
amazon | linux | exim-mysql | p-cpe:/a:amazon:linux:exim-mysql |
amazon | linux | exim-pgsql | p-cpe:/a:amazon:linux:exim-pgsql |
amazon | linux | cpe:/o:amazon:linux |