Vulnerabilities > CVE-2018-1000656 - Improper Input Validation vulnerability in multiple products

047910
CVSS 7.5 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
palletsprojects
netapp
CWE-20
nessus
NVD
Published: 2018-08-20
Updated: 2020-06-09

Summary

The Pallets Project flask version Before 0.12.3 contains a CWE-20: Improper Input Validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. This vulnerability appears to have been fixed in 0.12.3. NOTE: this may overlap CVE-2019-1010083.

Vulnerable Configurations

Part Description Count
Application
Palletsprojects
23
Application
Netapp
3

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Server Side Include (SSI) Injection
    An attacker can use Server Side Include (SSI) Injection to send code to a web application that then gets executed by the web server. Doing so enables the attacker to achieve similar results to Cross Site Scripting, viz., arbitrary code execution and information disclosure, albeit on a more limited scale, since the SSI directives are nowhere near as powerful as a full-fledged scripting language. Nonetheless, the attacker can conveniently gain access to sensitive files, such as password files, and execute shell commands.
  • Cross Zone Scripting
    An attacker is able to cause a victim to load content into their web-browser that bypasses security zone controls and gain access to increased privileges to execute scripting code or other web objects such as unsigned ActiveX controls or applets. This is a privilege elevation attack targeted at zone-based web-browser security. In a zone-based model, pages belong to one of a set of zones corresponding to the level of privilege assigned to that page. Pages in an untrusted zone would have a lesser level of access to the system and/or be restricted in the types of executable content it was allowed to invoke. In a cross-zone scripting attack, a page that should be assigned to a less privileged zone is granted the privileges of a more trusted zone. This can be accomplished by exploiting bugs in the browser, exploiting incorrect configuration in the zone controls, through a cross-site scripting attack that causes the attackers' content to be treated as coming from a more trusted page, or by leveraging some piece of system functionality that is accessible from both the trusted and less trusted zone. This attack differs from "Restful Privilege Escalation" in that the latter correlates to the inadequate securing of RESTful access methods (such as HTTP DELETE) on the server, while cross-zone scripting attacks the concept of security zones as implemented by a browser.
  • Cross Site Scripting through Log Files
    An attacker may leverage a system weakness where logs are susceptible to log injection to insert scripts into the system's logs. If these logs are later viewed by an administrator through a thin administrative interface and the log data is not properly HTML encoded before being written to the page, the attackers' scripts stored in the log will be executed in the administrative interface with potentially serious consequences. This attack pattern is really a combination of two other attack patterns: log injection and stored cross site scripting.
  • Command Line Execution through SQL Injection
    An attacker uses standard SQL injection methods to inject data into the command line for execution. This could be done directly through misuse of directives such as MSSQL_xp_cmdshell or indirectly through injection of data into the database that would be interpreted as shell commands. Sometime later, an unscrupulous backend application (or could be part of the functionality of the same application) fetches the injected data stored in the database and uses this data as command line arguments without performing proper validation. The malicious data escapes that data plane by spawning new commands to be executed on the host.

Nessus

  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2019-1112.NASL
    descriptionThis update for python-Flask to version 0.12.4 fixes the following issues : Security issue fixed : - CVE-2018-1000656: Fixed an improper input validation vulnerability in flask that can result in Large amount of memory usage possibly leading to denial of service. (bsc#1106279) This update was imported from the SUSE:SLE-15:Update update project.
    last seen2020-06-01
    modified2020-06-02
    plugin id123659
    published2019-04-03
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/123659
    titleopenSUSE Security Update : python-Flask (openSUSE-2019-1112)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from openSUSE Security Update openSUSE-2019-1112.
#
# The text description of this plugin is (C) SUSE LLC.
#

include("compat.inc");

if (description)
{
  script_id(123659);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/27");

  script_cve_id("CVE-2018-1000656");

  script_name(english:"openSUSE Security Update : python-Flask (openSUSE-2019-1112)");
  script_summary(english:"Check for the openSUSE-2019-1112 patch");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote openSUSE host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"This update for python-Flask to version 0.12.4 fixes the following
issues :

Security issue fixed :

  - CVE-2018-1000656: Fixed an improper input validation
    vulnerability in flask that can result in Large amount
    of memory usage possibly leading to denial of service.
    (bsc#1106279)

This update was imported from the SUSE:SLE-15:Update update project."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1106279"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected python-Flask packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/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:novell:opensuse:python2-Flask");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:python3-Flask");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:15.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/04/02");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/04/03");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"SuSE Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/SuSE/release", "Host/SuSE/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/SuSE/release");
if (isnull(release) || release =~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "openSUSE");
if (release !~ "^(SUSE15\.0)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "15.0", release);
if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);



flag = 0;

if ( rpm_check(release:"SUSE15.0", reference:"python2-Flask-0.12.4-lp150.2.3.1") ) flag++;
if ( rpm_check(release:"SUSE15.0", reference:"python3-Flask-0.12.4-lp150.2.3.1") ) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "python2-Flask / python3-Flask");
}
  • NASL familyRed Hat Local Security Checks
    NASL idREDHAT-RHSA-2020-0870.NASL
    descriptionThe remote Redhat Enterprise Linux 7 host has a package installed that is affected by a vulnerability as referenced in the RHSA-2020:0870 advisory. - python-flask: Denial of Service via crafted JSON file (CVE-2018-1000656) Note that Nessus has not tested for this issue but has instead relied only on the application
    last seen2020-04-23
    modified2020-03-18
    plugin id134674
    published2020-03-18
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/134674
    titleRHEL 7 : python-flask (RHSA-2020:0870)
    code
    #
# (C) Tenable Network Security, Inc.
#

# The descriptive text and package checks in this plugin were
# extracted from Red Hat Security Advisory RHSA-2020:0870. The text
# itself is copyright (C) Red Hat, Inc.
#


include('compat.inc');

if (description)
{
  script_id(134674);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/21");

  script_cve_id("CVE-2018-1000656");
  script_xref(name:"RHSA", value:"2020:0870");

  script_name(english:"RHEL 7 : python-flask (RHSA-2020:0870)");
  script_summary(english:"Checks the rpm output for the updated package");

  script_set_attribute(attribute:"synopsis", value:
"The remote Red Hat host is missing a security update.");
  script_set_attribute(attribute:"description", value:
"The remote Redhat Enterprise Linux 7 host has a package installed that is affected by a vulnerability as referenced in
the RHSA-2020:0870 advisory.

  - python-flask: Denial of Service via crafted JSON file
    (CVE-2018-1000656)

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://cwe.mitre.org/data/definitions/20.html");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/errata/RHSA-2020:0870");
  script_set_attribute(attribute:"see_also", value:"https://access.redhat.com/security/cve/CVE-2018-1000656");
  script_set_attribute(attribute:"solution", value:
"Update the affected python-flask package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/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:"cvss_score_source", value:"CVE-2018-1000656");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_cwe_id(20);

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/03/17");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/03/18");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:redhat:rhel_extras_other:7");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:7");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:python-flask");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"Red Hat Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list", "Host/cpu");

  exit(0);
}


include('audit.inc');
include('global_settings.inc');
include('misc_func.inc');
include('rpm.inc');

if (!get_kb_item('Host/local_checks_enabled')) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item('Host/RedHat/release');
if (isnull(release) || 'Red Hat' >!< release) audit(AUDIT_OS_NOT, 'Red Hat');
os_ver = pregmatch(pattern: "Red Hat Enterprise Linux.*release ([0-9]+(\.[0-9]+)?)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, 'Red Hat');
os_ver = os_ver[1];
if (! preg(pattern:"^7([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, 'Red Hat 7.x', 'Red Hat ' + os_ver);

if (!get_kb_item('Host/RedHat/rpm-list')) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item('Host/cpu');
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ('x86_64' >!< cpu && cpu !~ "^i[3-6]86$" && 's390' >!< cpu && 'aarch64' >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, 'Red Hat', cpu);

pkgs = [
    {'reference':'python-flask-0.10.1-5.el7_7', 'release':'7', 'epoch':'1'}
];

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

if (flag)
{
  security_report_v4(
      port       : 0,
      severity   : SECURITY_WARNING,
      extra      : rpm_report_get() + redhat_report_package_caveat()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, 'python-flask');
}
  • NASL familyCGI abuses
    NASL idFLASK_0_12_3.NASL
    descriptionThe version of Pallets Flask on the remote host is prior to 0.12.3. It is, therefore, affected by a denial of service vulnerability in the JSON decoding process due to improper input validation. An unauthenticated attacker can exploit this issue by providing JSON data in a non-text related encoding, which could result in unexpected memory use.
    last seen2020-06-01
    modified2020-06-02
    plugin id119778
    published2018-12-19
    reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/119778
    titleFlask < 0.12.3 Denial of Service Vulnerability
    code
    #
# (C) Tenable Network Security, Inc.
#

include("compat.inc");

if (description)
{
  script_id(119778);
  script_version("1.2");
  script_cvs_date("Date: 2019/10/31 15:18:51");

  script_cve_id("CVE-2018-1000656");

  script_name(english:"Flask < 0.12.3 Denial of Service Vulnerability");
  script_summary(english:"Checks the version of Flask.");

  script_set_attribute(attribute:"synopsis", value:
"A web development framework on the remote host is affected by
a denial of service vulnerability.");
  script_set_attribute(attribute:"description", value:
"The version of Pallets Flask on the remote host is prior to 0.12.3. 
It is, therefore, affected by a denial of service vulnerability in
the JSON decoding process due to improper input validation. An 
unauthenticated attacker can exploit this issue by providing JSON 
data in a non-text related encoding, which could result in unexpected 
memory use.");
  script_set_attribute(attribute:"see_also", value:"https://github.com/pallets/flask/releases/tag/0.12.3");
  script_set_attribute(attribute:"see_also", value:"https://nvd.nist.gov/vuln/detail/CVE-2018-1000656");
  script_set_attribute(attribute:"solution", value:
"Upgrade to Flask version 0.12.3 or later.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/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:"cvss_score_source", value:"CVE-2018-1000656");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/04/26");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/04/26");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/12/19");

  script_set_attribute(attribute:"plugin_type", value:"remote");
  script_set_attribute(attribute:"cpe", value:"x-cpe:/a:python-flask:-");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"CGI abuses");

  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("python_flask_installed_nix.nbin");
  script_require_keys("installed_sw/python-flask");

  exit(0);
}

include("audit.inc");
include("global_settings.inc");
include("misc_func.inc");
include("vcf.inc");

app = vcf::get_app_info(app:"python-flask");

constraints = [{"fixed_version" : "0.12.3"}];

vcf::check_version_and_report(app_info:app, constraints:constraints, severity:SECURITY_WARNING, strict:FALSE);
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-1892.NASL
    descriptionFlask, a micro web framework for Python contains a CWE-20: Improper Input Validation vulnerability that can result in Large amount of memory usage possibly leading to denial of service. This attack appear to be exploitable via Attacker provides JSON data in incorrect encoding. For Debian 8
    last seen2020-06-01
    modified2020-06-02
    plugin id128038
    published2019-08-21
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/128038
    titleDebian DLA-1892-1 : flask security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-1892-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(128038);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/02");

  script_cve_id("CVE-2018-1000656");

  script_name(english:"Debian DLA-1892-1 : flask security update");
  script_summary(english:"Checks dpkg output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"Flask, a micro web framework for Python contains a CWE-20: Improper
Input Validation vulnerability that can result in Large amount of
memory usage possibly leading to denial of service. This attack appear
to be exploitable via Attacker provides JSON data in incorrect
encoding.

For Debian 8 'Jessie', this problem has been fixed in version
0.10.1-2+deb8u1.

We recommend that you upgrade your flask packages.

NOTE: Tenable Network Security has extracted the preceding description
block directly from the DLA security advisory. Tenable has attempted
to automatically clean and format it as much as possible without
introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://lists.debian.org/debian-lts-announce/2019/08/msg00025.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/flask"
  );
  script_set_attribute(attribute:"solution", value:"Upgrade the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/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:debian:debian_linux:python-flask");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-flask-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3-flask");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/08/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/08/21");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Debian Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("debian_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;
if (deb_check(release:"8.0", prefix:"python-flask", reference:"0.10.1-2+deb8u1")) flag++;
if (deb_check(release:"8.0", prefix:"python-flask-doc", reference:"0.10.1-2+deb8u1")) flag++;
if (deb_check(release:"8.0", prefix:"python3-flask", reference:"0.10.1-2+deb8u1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:deb_report_get());
  else security_warning(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4378-1.NASL
    descriptionIt was discovered that Flask incorrectly handled certain inputs. An attacker could possibly use this issue to cause a denial of service. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-06
    modified2020-06-02
    plugin id137044
    published2020-06-02
    reporterUbuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/137044
    titleUbuntu 16.04 LTS / 18.04 LTS : flask vulnerability (USN-4378-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4378-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(137044);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/05");

  script_cve_id("CVE-2018-1000656");
  script_xref(name:"USN", value:"4378-1");

  script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS : flask vulnerability (USN-4378-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis",
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description",
    value:
"It was discovered that Flask incorrectly handled certain inputs. An
attacker could possibly use this issue to cause a denial of service.

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. Tenable
has attempted to automatically clean and format it as much as possible
without introducing additional issues."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://usn.ubuntu.com/4378-1/"
  );
  script_set_attribute(
    attribute:"solution",
    value:"Update the affected python-flask and / or python3-flask packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
  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:N/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:canonical:ubuntu_linux:python-flask");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-flask");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:14.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/02");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("misc_func.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(14\.04|16\.04|18\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 14.04 / 16.04 / 18.04", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) audit(AUDIT_PACKAGE_LIST_MISSING);

cpu = get_kb_item("Host/cpu");
if (isnull(cpu)) audit(AUDIT_UNKNOWN_ARCH);
if ("x86_64" >!< cpu && cpu !~ "^i[3-6]86$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Ubuntu", cpu);

flag = 0;

if (ubuntu_check(osver:"16.04", pkgname:"python-flask", pkgver:"0.10.1-2ubuntu0.1")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"python3-flask", pkgver:"0.10.1-2ubuntu0.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"python-flask", pkgver:"0.12.2-3ubuntu0.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"python3-flask", pkgver:"0.12.2-3ubuntu0.1")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "python-flask / python3-flask");
}

Redhat

rpmspython-flask-1:0.10.1-5.el7_7

References