Amazon Linux 2 : python / python3 (ALAS-2020-1471)

2020-08-06T00:00:00
ID AL2_ALAS-2020-1471.NASL
Type nessus
Reporter This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
Modified 2020-08-10T00:00:00

Description

Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7 through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct Regular Expression Denial of Service (ReDoS) attacks against a client because of urllib.request.AbstractBasicAuthHandler catastrophic backtracking. (CVE-2020-8492)

                                        
                                            #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALAS-2020-1471.
#

include("compat.inc");

if (description)
{
  script_id(139339);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/08/10");

  script_cve_id("CVE-2020-8492");
  script_xref(name:"ALAS", value:"2020-1471");

  script_name(english:"Amazon Linux 2 : python / python3 (ALAS-2020-1471)");
  script_summary(english:"Checks rpm output for the updated packages");

  script_set_attribute(
    attribute:"synopsis",
    value:"The remote Amazon Linux 2 host is missing a security update."
  );
  script_set_attribute(
    attribute:"description",
    value:
"Python 2.7 through 2.7.17, 3.5 through 3.5.9, 3.6 through 3.6.10, 3.7
through 3.7.6, and 3.8 through 3.8.1 allows an HTTP server to conduct
Regular Expression Denial of Service (ReDoS) attacks against a client
because of urllib.request.AbstractBasicAuthHandler catastrophic
backtracking. (CVE-2020-8492)"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://alas.aws.amazon.com/AL2/ALAS-2020-1471.html"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Run 'yum update python' to update your system.

Run 'yum update python3' to update your system."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:N/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:R/S:U/C:N/I:N/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:amazon:linux:python");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-test");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-debug");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-debuginfo");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-devel");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-libs");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-test");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-tkinter");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:python3-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tkinter");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/01/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/08/05");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/08/06");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2020 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 != "2")
{
  if (os_ver == 'A') os_ver = 'AMI';
  audit(AUDIT_OS_NOT, "Amazon Linux 2", "Amazon Linux " + os_ver);
}

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


flag = 0;
if (rpm_check(release:"AL2", reference:"python-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-debug-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-debuginfo-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-devel-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-libs-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-test-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python-tools-2.7.18-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-debug-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-debuginfo-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-devel-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-libs-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-test-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-tkinter-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"python3-tools-3.7.8-1.amzn2.0.1")) flag++;
if (rpm_check(release:"AL2", reference:"tkinter-2.7.18-1.amzn2.0.1")) 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, "python / python-debug / python-debuginfo / python-devel / etc");
}