Amazon Linux AMI : tomcat8 (ALAS-2021-1491)

##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2021-1491.
##

include('compat.inc');

if (description)
{
  script_id(148132);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/05");

  script_cve_id("CVE-2020-9484", "CVE-2021-25122");
  script_xref(name:"ALAS", value:"2021-1491");
  script_xref(name:"CEA-ID", value:"CEA-2021-0004");

  script_name(english:"Amazon Linux AMI : tomcat8 (ALAS-2021-1491)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux AMI host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of tomcat8 installed on the remote host is prior to 8.5.63-1.87. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS-2021-1491 advisory.

  - When using Apache Tomcat versions 10.0.0-M1 to 10.0.0-M4, 9.0.0.M1 to 9.0.34, 8.5.0 to 8.5.54 and 7.0.0 to
    7.0.103 if a) an attacker is able to control the contents and name of a file on the server; and b) the
    server is configured to use the PersistenceManager with a FileStore; and c) the PersistenceManager is
    configured with sessionAttributeValueClassNameFilter=null (the default unless a SecurityManager is used)
    or a sufficiently lax filter to allow the attacker provided object to be deserialized; and d) the attacker
    knows the relative file path from the storage location used by FileStore to the file the attacker has
    control over; then, using a specifically crafted request, the attacker will be able to trigger remote code
    execution via deserialization of the file under their control. Note that all of conditions a) to d) must
    be true for the attack to succeed. (CVE-2020-9484)

  - When responding to new h2c connection requests, Apache Tomcat versions 10.0.0-M1 to 10.0.0, 9.0.0.M1 to
    9.0.41 and 8.5.0 to 8.5.61 could duplicate request headers and a limited amount of request body from one
    request to another meaning user A and user B could both see the results of user A's request.
    (CVE-2021-25122)

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version
number.");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/ALAS-2021-1491.html");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/CVE-2020-9484");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/CVE-2021-25122");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update tomcat8' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:N/A:N");
  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:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:P/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2021-25122");

  script_set_attribute(attribute:"exploitability_ease", value:"Exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"true");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/05/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2021/03/23");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/03/25");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-admin-webapps");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-docs-webapp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-el-3.0-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-javadoc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-jsp-2.3-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-lib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-log4j");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-servlet-3.1-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat8-webapps");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Amazon Linux Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2021-2022 and is owned by Tenable, Inc. or an Affiliate thereof.");

  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);

pkgs = [
    {'reference':'tomcat8-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-admin-webapps-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-docs-webapp-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-el-3.0-api-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-javadoc-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-jsp-2.3-api-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-lib-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-log4j-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-servlet-3.1-api-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat8-webapps-8.5.63-1.87.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE}
];

flag = 0;
foreach package_array ( pkgs ) {
  reference = NULL;
  release = NULL;
  cpu = NULL;
  el_string = NULL;
  rpm_spec_vers_cmp = NULL;
  allowmaj = NULL;
  if (!empty_or_null(package_array['reference'])) reference = package_array['reference'];
  if (!empty_or_null(package_array['release'])) release = package_array['release'];
  if (!empty_or_null(package_array['cpu'])) cpu = package_array['cpu'];
  if (!empty_or_null(package_array['el_string'])) el_string = package_array['el_string'];
  if (!empty_or_null(package_array['rpm_spec_vers_cmp'])) rpm_spec_vers_cmp = package_array['rpm_spec_vers_cmp'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (reference && release) {
    if (rpm_check(release:release, cpu:cpu, reference:reference, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
  }
}

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "tomcat8 / tomcat8-admin-webapps / tomcat8-docs-webapp / etc");
}