Vulnerabilities > CVE-2017-1000433 - Improper Authentication vulnerability in multiple products

047910
CVSS 8.1 - HIGH
Attack vector
NETWORK
Attack complexity
HIGH
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
high complexity
pysaml2-project
debian
CWE-287
nessus
NVD
Published: 2018-01-02
Updated: 2024-11-21

Summary

pysaml2 version 4.4.0 and older accept any password when run with python optimizations enabled. This allows attackers to log in as any user without knowing their password.

Vulnerable Configurations

Part Description Count
Application
Pysaml2_Project
22
OS
Debian
2

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Authentication Abuse
    An attacker obtains unauthorized access to an application, service or device either through knowledge of the inherent weaknesses of an authentication mechanism, or by exploiting a flaw in the authentication scheme's implementation. In such an attack an authentication mechanism is functioning but a carefully controlled sequence of events causes the mechanism to grant access to the attacker. This attack may exploit assumptions made by the target's authentication procedures, such as assumptions regarding trust relationships or assumptions regarding the generation of secret values. This attack differs from Authentication Bypass attacks in that Authentication Abuse allows the attacker to be certified as a valid user through illegitimate means, while Authentication Bypass allows the user to access protected material without ever being certified as an authenticated user. This attack does not rely on prior sessions established by successfully authenticating users, as relied upon for the "Exploitation of Session Variables, Resource IDs and other Trusted Credentials" attack patterns.
  • Exploiting Trust in Client (aka Make the Client Invisible)
    An attack of this type exploits a programs' vulnerabilities in client/server communication channel authentication and data integrity. It leverages the implicit trust a server places in the client, or more importantly, that which the server believes is the client. An attacker executes this type of attack by placing themselves in the communication channel between client and server such that communication directly to the server is possible where the server believes it is communicating only with a valid client. There are numerous variations of this type of attack.
  • Utilizing REST's Trust in the System Resource to Register Man in the Middle
    This attack utilizes a REST(REpresentational State Transfer)-style applications' trust in the system resources and environment to place man in the middle once SSL is terminated. Rest applications premise is that they leverage existing infrastructure to deliver web services functionality. An example of this is a Rest application that uses HTTP Get methods and receives a HTTP response with an XML document. These Rest style web services are deployed on existing infrastructure such as Apache and IIS web servers with no SOAP stack required. Unfortunately from a security standpoint, there frequently is no interoperable identity security mechanism deployed, so Rest developers often fall back to SSL to deliver security. In large data centers, SSL is typically terminated at the edge of the network - at the firewall, load balancer, or router. Once the SSL is terminated the HTTP request is in the clear (unless developers have hashed or encrypted the values, but this is rare). The attacker can utilize a sniffer such as Wireshark to snapshot the credentials, such as username and password that are passed in the clear once SSL is terminated. Once the attacker gathers these credentials, they can submit requests to the web service provider just as authorized user do. There is not typically an authentication on the client side, beyond what is passed in the request itself so once this is compromised, then this is generally sufficient to compromise the service's authentication scheme.
  • Man in the Middle Attack
    This type of attack targets the communication between two components (typically client and server). The attacker places himself in the communication channel between the two components. Whenever one component attempts to communicate with the other (data flow, authentication challenges, etc.), the data first goes to the attacker, who has the opportunity to observe or alter it, and it is then passed on to the other component as if it was never intercepted. This interposition is transparent leaving the two compromised components unaware of the potential corruption or leakage of their communications. The potential for Man-in-the-Middle attacks yields an implicit lack of trust in communication or identify between two components.

Nessus

  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201801-11.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201801-11 (PySAML2: Security bypass) It was found that the PySAML2 relies on an assert statement to check the user’s password. A python optimizations might remove this assertion. Impact : A remote attacker could bypass security restrictions and access any application which is using PySAML2 for authentication. Workaround : Disable python optimizations.
    last seen2020-06-01
    modified2020-06-02
    plugin id105755
    published2018-01-12
    reporterThis script is Copyright (C) 2018 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/105755
    titleGLSA-201801-11 : PySAML2: Security bypass
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 201801-11.
#
# The advisory text is Copyright (C) 2001-2018 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/3.0/
#

include("compat.inc");

if (description)
{
  script_id(105755);
  script_version("$Revision: 3.3 $");
  script_cvs_date("$Date: 2018/01/26 17:15:58 $");

  script_cve_id("CVE-2017-1000433");
  script_xref(name:"GLSA", value:"201801-11");

  script_name(english:"GLSA-201801-11 : PySAML2: Security bypass");
  script_summary(english:"Checks for updated package(s) in /var/db/pkg");

  script_set_attribute(
    attribute:"synopsis", 
    value:
"The remote Gentoo host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The remote host is affected by the vulnerability described in GLSA-201801-11
(PySAML2: Security bypass)

    It was found that the PySAML2 relies on an assert statement to check the
      user’s password. A python optimizations might remove this assertion.
  
Impact :

    A remote attacker could bypass security restrictions and access any
      application which is using PySAML2 for authentication.
  
Workaround :

    Disable python optimizations."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://security.gentoo.org/glsa/201801-11"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All PySAML2 4.0 users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=dev-python/pysaml2-4.0.2-r3'
    All PySAML2 4.5 users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=dev-python/pysaml2-4.5.0'"
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:H/I:H/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:pysaml2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2018/01/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/12");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018 Tenable Network Security, Inc.");
  script_family(english:"Gentoo Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");

  exit(0);
}


include("audit.inc");
include("global_settings.inc");
include("qpkg.inc");

if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (qpkg_check(package:"dev-python/pysaml2", unaffected:make_list("ge 4.0.2-r3", "ge 4.5.0"), vulnerable:make_list("lt 4.0.2-r3", "lt 4.5.0"))) flag++;

if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:qpkg_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = qpkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "PySAML2");
}
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-3520-1.NASL
    descriptionIt was discovered that PySAML2 incorrectly accepted any password when run with python optimizations enabled. An attacker could use this issue to authenticate as any user without a valid password. 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 seen2020-06-01
    modified2020-06-02
    plugin id105688
    published2018-01-09
    reporterUbuntu Security Notice (C) 2018-2019 Canonical, Inc. / NASL script (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/105688
    titleUbuntu 16.04 LTS / 17.04 / 17.10 : python-pysaml2 vulnerability (USN-3520-1)
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-3520-1. 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(105688);
  script_version("3.8");
  script_cvs_date("Date: 2019/09/18 12:31:47");

  script_cve_id("CVE-2017-1000433");
  script_xref(name:"USN", value:"3520-1");

  script_name(english:"Ubuntu 16.04 LTS / 17.04 / 17.10 : python-pysaml2 vulnerability (USN-3520-1)");
  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 PySAML2 incorrectly accepted any password when
run with python optimizations enabled. An attacker could use this
issue to authenticate as any user without a valid password.

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/3520-1/"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected python-pysaml2 and / or python3-pysaml2 packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/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:H/PR:N/UI:N/S:U/C:H/I:H/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:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-pysaml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-pysaml2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:16.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:17.04");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:17.10");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/01/02");
  script_set_attribute(attribute:"patch_publication_date", value:"2018/01/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/09");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2018-2019 Canonical, Inc. / NASL script (C) 2018-2019 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:"^(16\.04|17\.04|17\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04 / 17.04 / 17.10", "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-pysaml2", pkgver:"3.0.0-3ubuntu1.16.04.3")) flag++;
if (ubuntu_check(osver:"16.04", pkgname:"python3-pysaml2", pkgver:"3.0.0-3ubuntu1.16.04.3")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"python-pysaml2", pkgver:"3.0.0-3ubuntu1.17.04.3")) flag++;
if (ubuntu_check(osver:"17.04", pkgname:"python3-pysaml2", pkgver:"3.0.0-3ubuntu1.17.04.3")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"python-pysaml2", pkgver:"3.0.0-3ubuntu2.2")) flag++;
if (ubuntu_check(osver:"17.10", pkgname:"python3-pysaml2", pkgver:"3.0.0-3ubuntu2.2")) 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-pysaml2 / python3-pysaml2");
}
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-1410.NASL
    descriptionPysaml2, a Python implementation of the Security Assertion Markup Language, would accept any password when run with Python optimizations enabled. This allows attackers to log in as any user without knowing their password. For Debian 8
    last seen2020-06-01
    modified2020-06-02
    plugin id110819
    published2018-07-02
    reporterThis script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/110819
    titleDebian DLA-1410-1 : python-pysaml2 security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-1410-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(110819);
  script_version("1.3");
  script_cvs_date("Date: 2018/08/08 12:52:14");

  script_cve_id("CVE-2017-1000433");

  script_name(english:"Debian DLA-1410-1 : python-pysaml2 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:
"Pysaml2, a Python implementation of the Security Assertion Markup
Language, would accept any password when run with Python optimizations
enabled. This allows attackers to log in as any user without knowing
their password.

For Debian 8 'Jessie', this issue has been fixed in version
2.0.0-1+deb8u2.

We recommend that you upgrade your python-pysaml2 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/2018/07/msg00000.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/python-pysaml2"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Upgrade the affected python-pysaml2, and python-pysaml2-doc packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:P/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:H/PR:N/UI:N/S:U/C:H/I:H/A:H");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-pysaml2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-pysaml2-doc");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"patch_publication_date", value:"2018/07/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/07/02");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018 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-pysaml2", reference:"2.0.0-1+deb8u2")) flag++;
if (deb_check(release:"8.0", prefix:"python-pysaml2-doc", reference:"2.0.0-1+deb8u2")) 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");

References