Amazon Linux AMI : tomcat7 (ALAS-2021-1493)

##
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Amazon Linux AMI Security Advisory ALAS-2021-1493.
##

include('compat.inc');

if (description)
{
  script_id(148378);
  script_version("1.4");
  script_set_attribute(attribute:"plugin_modification_date", value:"2022/12/05");

  script_cve_id("CVE-2020-9484", "CVE-2020-9494", "CVE-2021-25329");
  script_xref(name:"ALAS", value:"2021-1493");
  script_xref(name:"CEA-ID", value:"CEA-2021-0004");

  script_name(english:"Amazon Linux AMI : tomcat7 (ALAS-2021-1493)");

  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 tomcat7 installed on the remote host is prior to 7.0.108-1.40. It is, therefore, affected by multiple
vulnerabilities as referenced in the ALAS-2021-1493 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)

  - Apache Traffic Server 6.0.0 to 6.2.3, 7.0.0 to 7.1.10, and 8.0.0 to 8.0.7 is vulnerable to certain types
    of HTTP/2 HEADERS frames that can cause the server to allocate a large amount of memory and spin the
    thread. (CVE-2020-9494)

  - The fix for CVE-2020-9484 was incomplete. When using Apache Tomcat 10.0.0-M1 to 10.0.0, 9.0.0.M1 to
    9.0.41, 8.5.0 to 8.5.61 or 7.0.0. to 7.0.107 with a configuration edge case that was highly unlikely to be
    used, the Tomcat instance was still vulnerable to CVE-2020-9494. Note that both the previously published
    prerequisites for CVE-2020-9484 and the previously published mitigations for CVE-2020-9484 also apply to
    this issue. (CVE-2021-25329)

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-2021-1493.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-2021-25329");
  script_set_attribute(attribute:"solution", value:
"Run 'yum update tomcat7' to update your system.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/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:L/AC:H/PR:L/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:"cvss_score_source", value:"CVE-2021-25329");

  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:"2021/04/07");
  script_set_attribute(attribute:"plugin_publication_date", value:"2021/04/07");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-admin-webapps");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-docs-webapp");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-el-2.2-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-javadoc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-jsp-2.2-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-lib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-log4j");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-servlet-3.0-api");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:amazon:linux:tomcat7-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':'tomcat7-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-admin-webapps-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-docs-webapp-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-el-2.2-api-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-javadoc-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-jsp-2.2-api-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-lib-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-log4j-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-servlet-3.0-api-7.0.108-1.40.amzn1', 'release':'ALA', 'rpm_spec_vers_cmp':TRUE},
    {'reference':'tomcat7-webapps-7.0.108-1.40.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, "tomcat7 / tomcat7-admin-webapps / tomcat7-docs-webapp / etc");
}