Vulnerabilities > CVE-2018-10894 - Improper Certificate Validation vulnerability in Redhat Keycloak and Single Sign-On

047910
CVSS 5.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
NONE
network
low complexity
redhat
CWE-295
nessus

Summary

It was found that SAML authentication in Keycloak 3.4.3.Final incorrectly authenticated expired certificates. A malicious user could use this to access unauthorized data or possibly conduct further attacks.

Vulnerable Configurations

Part Description Count
Application
Redhat
2
OS
Redhat
2

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Creating a Rogue Certificate Authority Certificate
    An attacker exploits a weakness in the MD5 hash algorithm (weak collision resistance) to generate a certificate signing request (CSR) that contains collision blocks in the "to be signed" part. The attacker specially crafts two different, but valid X.509 certificates that when hashed with the MD5 algorithm would yield the same value. The attacker then sends the CSR for one of the certificates to the Certification Authority which uses the MD5 hashing algorithm. That request is completely valid and the Certificate Authority issues an X.509 certificate to the attacker which is signed with its private key. An attacker then takes that signed blob and inserts it into another X.509 certificate that the attacker generated. Due to the MD5 collision, both certificates, though different, hash to the same value and so the signed blob works just as well in the second certificate. The net effect is that the attackers' second X.509 certificate, which the Certification Authority has never seen, is now signed and validated by that Certification Authority. To make the attack more interesting, the second certificate could be not just a regular certificate, but rather itself a signing certificate. Thus the attacker is able to start their own Certification Authority that is anchored in its root of trust in the legitimate Certification Authority that has signed the attackers' first X.509 certificate. If the original Certificate Authority was accepted by default by browsers, so will now the Certificate Authority set up by the attacker and of course any certificates that it signs. So the attacker is now able to generate any SSL certificates to impersonate any web server, and the user's browser will not issue any warning to the victim. This can be used to compromise HTTPS communications and other types of systems where PKI and X.509 certificates may be used (e.g., VPN, IPSec) .

Nessus

  • NASL familyRed Hat Local Security Checks
    NASL idREDHAT-RHSA-2018-3592.NASL
    descriptionNew Red Hat Single Sign-On 7.2.5 packages are now available for Red Hat Enterprise Linux 6. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. Red Hat Single Sign-On 7.2 is a standalone server, based on the Keycloak project, that provides authentication and standards-based single sign-on capabilities for web and mobile applications. This release of Red Hat Single Sign-On 7.2.5 serves as a replacement for Red Hat Single Sign-On 7.2.4, and includes bug fixes and enhancements, which are documented in the Release Notes document linked to in the References. Security Fix(es) : * keycloak: auth permitted with expired certs in SAML client (CVE-2018-10894) * keycloak: XSS-Vulnerability with response_mode=form_post (CVE-2018-14655) * keycloak: Open Redirect in Login and Logout (CVE-2018-14658) * keycloak: brute force protection not working for the entire login workflow (CVE-2018-14657) For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section. The CVE-2018-10894 issue was discovered by Benjamin Berg (Red Hat).
    last seen2020-06-01
    modified2020-06-02
    plugin id118949
    published2018-11-14
    reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/118949
    titleRHEL 6 : Red Hat Single Sign-On 7.2.5 on RHEL 6 (RHSA-2018:3592)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from Red Hat Security Advisory RHSA-2018:3592. The text 
    # itself is copyright (C) Red Hat, Inc.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(118949);
      script_version("1.8");
      script_cvs_date("Date: 2019/10/24 15:35:46");
    
      script_cve_id("CVE-2018-10894", "CVE-2018-14637", "CVE-2018-14655", "CVE-2018-14657", "CVE-2018-14658");
      script_xref(name:"RHSA", value:"2018:3592");
    
      script_name(english:"RHEL 6 : Red Hat Single Sign-On 7.2.5 on RHEL 6 (RHSA-2018:3592)");
      script_summary(english:"Checks the rpm output for the updated packages");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:"The remote Red Hat host is missing one or more security updates."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "New Red Hat Single Sign-On 7.2.5 packages are now available for Red
    Hat Enterprise Linux 6.
    
    Red Hat Product Security has rated this update as having a security
    impact of Moderate. A Common Vulnerability Scoring System (CVSS) base
    score, which gives a detailed severity rating, is available for each
    vulnerability from the CVE link(s) in the References section.
    
    Red Hat Single Sign-On 7.2 is a standalone server, based on the
    Keycloak project, that provides authentication and standards-based
    single sign-on capabilities for web and mobile applications.
    
    This release of Red Hat Single Sign-On 7.2.5 serves as a replacement
    for Red Hat Single Sign-On 7.2.4, and includes bug fixes and
    enhancements, which are documented in the Release Notes document
    linked to in the References.
    
    Security Fix(es) :
    
    * keycloak: auth permitted with expired certs in SAML client
    (CVE-2018-10894)
    
    * keycloak: XSS-Vulnerability with response_mode=form_post
    (CVE-2018-14655)
    
    * keycloak: Open Redirect in Login and Logout (CVE-2018-14658)
    
    * keycloak: brute force protection not working for the entire login
    workflow (CVE-2018-14657)
    
    For more details about the security issue(s), including the impact, a
    CVSS score, and other related information, refer to the CVE page(s)
    listed in the References section.
    
    The CVE-2018-10894 issue was discovered by Benjamin Berg (Red Hat)."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/documentation/en-us/red_hat_single_sign_on/?"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/errata/RHSA-2018:3592"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/security/cve/cve-2018-10894"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/security/cve/cve-2018-14637"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/security/cve/cve-2018-14655"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/security/cve/cve-2018-14657"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://access.redhat.com/security/cve/cve-2018-14658"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "Update the affected rh-sso7-keycloak and / or rh-sso7-keycloak-server
    packages."
      );
      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:redhat:enterprise_linux:rh-sso7-keycloak");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:redhat:enterprise_linux:rh-sso7-keycloak-server");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:redhat:enterprise_linux:6");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2018/08/01");
      script_set_attribute(attribute:"patch_publication_date", value:"2018/11/13");
      script_set_attribute(attribute:"plugin_publication_date", value:"2018/11/14");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"Red Hat Local Security Checks");
    
      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:"^6([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Red Hat 6.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) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Red Hat", cpu);
    
    yum_updateinfo = get_kb_item("Host/RedHat/yum-updateinfo");
    if (!empty_or_null(yum_updateinfo)) 
    {
      rhsa = "RHSA-2018:3592";
      yum_report = redhat_generate_yum_updateinfo_report(rhsa:rhsa);
      if (!empty_or_null(yum_report))
      {
        security_report_v4(
          port       : 0,
          severity   : SECURITY_WARNING,
          extra      : yum_report 
        );
        exit(0);
      }
      else
      {
        audit_message = "affected by Red Hat security advisory " + rhsa;
        audit(AUDIT_OS_NOT, audit_message);
      }
    }
    else
    {
      flag = 0;
      if (rpm_check(release:"RHEL6", reference:"rh-sso7-keycloak-3.4.14-1.Final_redhat_00001.1.jbcs.el6")) flag++;
      if (rpm_check(release:"RHEL6", reference:"rh-sso7-keycloak-server-3.4.14-1.Final_redhat_00001.1.jbcs.el6")) 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, "rh-sso7-keycloak / rh-sso7-keycloak-server");
      }
    }
    
  • NASL familyRed Hat Local Security Checks
    NASL idREDHAT-RHSA-2018-3593.NASL
    descriptionNew Red Hat Single Sign-On 7.2.5 packages are now available for Red Hat Enterprise Linux 7. Red Hat Product Security has rated this update as having a security impact of Moderate. A Common Vulnerability Scoring System (CVSS) base score, which gives a detailed severity rating, is available for each vulnerability from the CVE link(s) in the References section. Red Hat Single Sign-On 7.2 is a standalone server, based on the Keycloak project, that provides authentication and standards-based single sign-on capabilities for web and mobile applications. This release of Red Hat Single Sign-On 7.2.5 serves as a replacement for Red Hat Single Sign-On 7.2.4, and includes bug fixes and enhancements, which are documented in the Release Notes document linked to in the References. Security Fix(es) : * keycloak: auth permitted with expired certs in SAML client (CVE-2018-10894) * keycloak: XSS-Vulnerability with response_mode=form_post (CVE-2018-14655) * keycloak: Open Redirect in Login and Logout (CVE-2018-14658) * keycloak: brute force protection not working for the entire login workflow (CVE-2018-14657) For more details about the security issue(s), including the impact, a CVSS score, and other related information, refer to the CVE page(s) listed in the References section. The CVE-2018-10894 issue was discovered by Benjamin Berg (Red Hat).
    last seen2020-06-01
    modified2020-06-02
    plugin id118950
    published2018-11-14
    reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/118950
    titleRHEL 7 : Red Hat Single Sign-On 7.2.5 on RHEL 7 (RHSA-2018:3593)

Redhat

advisories
  • rhsa
    idRHSA-2018:3592
  • rhsa
    idRHSA-2018:3593
  • rhsa
    idRHSA-2018:3595
  • rhsa
    idRHSA-2019:0877
rpms
  • rh-sso7-keycloak-0:3.4.14-1.Final_redhat_00001.1.jbcs.el6
  • rh-sso7-keycloak-server-0:3.4.14-1.Final_redhat_00001.1.jbcs.el6
  • rh-sso7-keycloak-0:3.4.14-1.Final_redhat_00001.1.jbcs.el7
  • rh-sso7-keycloak-server-0:3.4.14-1.Final_redhat_00001.1.jbcs.el7