Amazon Linux 2 : tomcat (ALASTOMCAT8.5-2023-012)

#%NASL_MIN_LEVEL 80900
##
# (C) Tenable, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux 2 Security Advisory ALASTOMCAT8.5-2023-012.
##

include('compat.inc');

if (description)
{
  script_id(182025);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2023/09/28");

  script_cve_id("CVE-2019-17569", "CVE-2020-1935", "CVE-2020-1938");
  script_xref(name:"CISA-KNOWN-EXPLOITED", value:"2022/03/17");
  script_xref(name:"IAVA", value:"2020-A-0328");
  script_xref(name:"IAVB", value:"2020-B-0010-S");
  script_xref(name:"CEA-ID", value:"CEA-2020-0021");

  script_name(english:"Amazon Linux 2 : tomcat (ALASTOMCAT8.5-2023-012)");

  script_set_attribute(attribute:"synopsis", value:
"The remote Amazon Linux 2 host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The version of tomcat installed on the remote host is prior to 8.5.51-1. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS2TOMCAT8.5-2023-012 advisory.

  - The refactoring present in Apache Tomcat 9.0.28 to 9.0.30, 8.5.48 to 8.5.50 and 7.0.98 to 7.0.99
    introduced a regression. The result of the regression was that invalid Transfer-Encoding headers were
    incorrectly processed leading to a possibility of HTTP Request Smuggling if Tomcat was located behind a
    reverse proxy that incorrectly handled the invalid Transfer-Encoding header in a particular manner. Such a
    reverse proxy is considered unlikely. (CVE-2019-17569)

  - In Apache Tomcat 9.0.0.M1 to 9.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99 the HTTP header parsing code used
    an approach to end-of-line parsing that allowed some invalid HTTP headers to be parsed as valid. This led
    to a possibility of HTTP Request Smuggling if Tomcat was located behind a reverse proxy that incorrectly
    handled the invalid Transfer-Encoding header in a particular manner. Such a reverse proxy is considered
    unlikely. (CVE-2020-1935)

  - When using the Apache JServ Protocol (AJP), care must be taken when trusting incoming connections to
    Apache Tomcat. Tomcat treats AJP connections as having higher trust than, for example, a similar HTTP
    connection. If such connections are available to an attacker, they can be exploited in ways that may be
    surprising. In Apache Tomcat 9.0.0.M1 to 9.0.0.30, 8.5.0 to 8.5.50 and 7.0.0 to 7.0.99, Tomcat shipped
    with an AJP Connector enabled by default that listened on all configured IP addresses. It was expected
    (and recommended in the security guide) that this Connector would be disabled if not required. This
    vulnerability report identified a mechanism that allowed: - returning arbitrary files from anywhere in the
    web application - processing any file in the web application as a JSP Further, if the web application
    allowed file upload and stored those files within the web application (or the attacker was able to control
    the content of the web application by some other means) then this, along with the ability to process a
    file as a JSP, made remote code execution possible. It is important to note that mitigation is only
    required if an AJP port is accessible to untrusted users. Users wishing to take a defence-in-depth
    approach and block the vector that permits returning arbitrary files and execution as JSP may upgrade to
    Apache Tomcat 9.0.31, 8.5.51 or 7.0.100 or later. A number of changes were made to the default AJP
    Connector configuration in 9.0.31 to harden the default configuration. It is likely that users upgrading
    to 9.0.31, 8.5.51 or 7.0.100 or later will need to make small changes to their configurations.
    (CVE-2020-1938)

Note that Nessus has not tested for these issues 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/AL2/ALASTOMCAT8.5-2023-012.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2019-17569.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2020-1935.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/cve/html/CVE-2020-1938.html");
  script_set_attribute(attribute:"see_also", value:"https://alas.aws.amazon.com/faqs.html");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update tomcat' 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:H/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:H/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2020-1938");

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

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/11");
  script_set_attribute(attribute:"patch_publication_date", value:"2023/08/21");
  script_set_attribute(attribute:"plugin_publication_date", value:"2023/09/27");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-admin-webapps");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-docs-webapp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-el-3.0-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-javadoc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-jsp-2.3-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-jsvc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-lib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-servlet-3.1-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat-webapps");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:amazon:linux:2");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"stig_severity", value:"I");
  script_end_attributes();

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

  script_copyright(english:"This script is Copyright (C) 2023 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("rpm.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);

var alas_release = get_kb_item("Host/AmazonLinux/release");
if (isnull(alas_release) || !strlen(alas_release)) audit(AUDIT_OS_NOT, "Amazon Linux");
var os_ver = pregmatch(pattern: "^AL(A|\d+|-\d+)", string:alas_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);

var pkgs = [
    {'reference':'tomcat-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-admin-webapps-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-docs-webapp-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-el-3.0-api-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-javadoc-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-jsp-2.3-api-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-jsvc-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-lib-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-servlet-3.1-api-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'},
    {'reference':'tomcat-webapps-8.5.51-1.amzn2', 'release':'AL2', 'rpm_spec_vers_cmp':TRUE, 'exists_check':'tomcat8.5'}
];

var flag = 0;
foreach var package_array ( pkgs ) {
  var reference = NULL;
  var _release = NULL;
  var sp = NULL;
  var _cpu = NULL;
  var el_string = NULL;
  var rpm_spec_vers_cmp = NULL;
  var epoch = NULL;
  var allowmaj = NULL;
  var exists_check = 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['sp'])) sp = package_array['sp'];
  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['epoch'])) epoch = package_array['epoch'];
  if (!empty_or_null(package_array['allowmaj'])) allowmaj = package_array['allowmaj'];
  if (!empty_or_null(package_array['exists_check'])) exists_check = package_array['exists_check'];
  if (reference && _release && (!exists_check || rpm_exists(release:_release, rpm:exists_check))) {
    if (rpm_check(release:_release, sp:sp, cpu:_cpu, reference:reference, epoch:epoch, el_string:el_string, rpm_spec_vers_cmp:rpm_spec_vers_cmp, allowmaj:allowmaj)) flag++;
  }
}

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