Vulnerabilities > CVE-2018-6916 - Use After Free vulnerability in Freebsd

047910
CVSS 9.8 - CRITICAL
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
network
low complexity
freebsd
CWE-416
critical
nessus

Summary

In FreeBSD before 11.1-STABLE, 11.1-RELEASE-p7, 10.4-STABLE, 10.4-RELEASE-p7, and 10.3-RELEASE-p28, the kernel does not properly validate IPsec packets coming from a trusted host. Additionally, a use-after-free vulnerability exists in the IPsec AH handling code. This issue could cause a system crash or other unpredictable results.

Vulnerable Configurations

Part Description Count
OS
Freebsd
31

Common Weakness Enumeration (CWE)

Nessus

  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_DCA7CED0279611E895ECA4BADB2F4699.NASL
    descriptionDue to a lack of strict checking, an attacker from a trusted host can send a specially constructed IP packet that may lead to a system crash. Additionally, a use-after-free vulnerability in the AH handling code could cause unpredictable results. Impact : Access to out of bounds or freed mbuf data can lead to a kernel panic or other unpredictable results.
    last seen2020-06-01
    modified2020-06-02
    plugin id108353
    published2018-03-15
    reporterThis script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/108353
    titleFreeBSD : FreeBSD -- ipsec validation and use-after-free (dca7ced0-2796-11e8-95ec-a4badb2f4699)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from the FreeBSD VuXML database :
    #
    # Copyright 2003-2018 Jacques Vidrine and contributors
    #
    # Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
    # HTML, PDF, PostScript, RTF and so forth) with or without modification,
    # are permitted provided that the following conditions are met:
    # 1. Redistributions of source code (VuXML) must retain the above
    #    copyright notice, this list of conditions and the following
    #    disclaimer as the first lines of this file unmodified.
    # 2. Redistributions in compiled form (transformed to other DTDs,
    #    published online in any format, converted to PDF, PostScript,
    #    RTF and other formats) must reproduce the above copyright
    #    notice, this list of conditions and the following disclaimer
    #    in the documentation and/or other materials provided with the
    #    distribution.
    # 
    # THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
    # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
    # THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
    # PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
    # BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
    # OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
    # OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
    # BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
    # WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
    # OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
    # EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(108353);
      script_version("1.5");
      script_cvs_date("Date: 2018/12/07  9:46:53");
    
      script_cve_id("CVE-2018-6916");
      script_xref(name:"FreeBSD", value:"SA-18:01.ipsec");
    
      script_name(english:"FreeBSD : FreeBSD -- ipsec validation and use-after-free (dca7ced0-2796-11e8-95ec-a4badb2f4699)");
      script_summary(english:"Checks for updated packages in pkg_info output");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:
    "The remote FreeBSD host is missing one or more security-related
    updates."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "Due to a lack of strict checking, an attacker from a trusted host can
    send a specially constructed IP packet that may lead to a system
    crash.
    
    Additionally, a use-after-free vulnerability in the AH handling code
    could cause unpredictable results. Impact : Access to out of bounds or
    freed mbuf data can lead to a kernel panic or other unpredictable
    results."
      );
      # https://vuxml.freebsd.org/freebsd/dca7ced0-2796-11e8-95ec-a4badb2f4699.html
      script_set_attribute(
        attribute:"see_also",
        value:"http://www.nessus.org/u?830ed0a6"
      );
      script_set_attribute(attribute:"solution", value:"Update the affected packages.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A: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_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:FreeBSD");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2018/03/07");
      script_set_attribute(attribute:"patch_publication_date", value:"2018/03/14");
      script_set_attribute(attribute:"plugin_publication_date", value:"2018/03/15");
      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:"FreeBSD Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info", "Settings/ParanoidReport");
    
      exit(0);
    }
    
    
    include("audit.inc");
    include("freebsd_package.inc");
    
    
    if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
    if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
    if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);
    
    
    if (report_paranoia < 2) audit(AUDIT_PARANOID);
    
    flag = 0;
    
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=11.1<11.1_7")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=10.4<10.4_7")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=10.3<10.3_28")) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_hole(port:0, extra:pkg_report_get());
      else security_hole(0);
      exit(0);
    }
    else audit(AUDIT_HOST_NOT, "affected");
    
  • NASL familyFirewalls
    NASL idPFSENSE_SA-18_03.NASL
    descriptionAccording to its self-reported version number, the remote pfSense install is a version prior to 2.4.3 It is, therefore, affected by multiple vulnerabilities as stated in the referenced vendor advisories.
    last seen2020-06-01
    modified2020-06-02
    plugin id109038
    published2018-04-13
    reporterThis script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/109038
    titlepfSense < 2.4.3 Multiple Vulnerabilities (SA-18_01 / SA-18_02 / SA-18_03) (Meltdown) (Spectre)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(109038);
      script_version("1.4");
      script_cvs_date("Date: 2018/07/25 14:27:29");
    
      script_cve_id("CVE-2017-5715", "CVE-2017-5754", "CVE-2018-6916");
      script_bugtraq_id(103513);
      script_xref(name:"FreeBSD", value:"SA-18:01.ipsec");
      script_xref(name:"FreeBSD", value:"SA-18:03.speculative_execution");
      script_xref(name:"IAVA", value:"2018-A-0019");
      script_xref(name:"IAVA", value:"2018-A-0020");
    
      script_name(english:"pfSense < 2.4.3 Multiple Vulnerabilities (SA-18_01 / SA-18_02 / SA-18_03) (Meltdown) (Spectre)");
      script_summary(english:"Checks the version of pfSense.");
    
      script_set_attribute(attribute:"synopsis", value:
    "The remote firewall host is affected by multiple vulnerabilities.");
      script_set_attribute(attribute:"description", value:
    "According to its self-reported version number, the remote pfSense
    install is a version prior to 2.4.3 It is, therefore, affected by 
    multiple vulnerabilities as stated in the referenced vendor
    advisories.");
      script_set_attribute(attribute:"see_also", value:"https://doc.pfsense.org/index.php/2.4.3_New_Features_and_Changes");
      # https://www.pfsense.org/security/advisories/pfSense-SA-18_01.packages.asc
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?9ac779c2");
      # https://www.pfsense.org/security/advisories/pfSense-SA-18_02.webgui.asc
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?d531aa61");
      # https://www.pfsense.org/security/advisories/pfSense-SA-18_03.webgui.asc
      script_set_attribute(attribute:"see_also", value:"http://www.nessus.org/u?4c483bc2");
      script_set_attribute(attribute:"solution", value:
    "Upgrade to pfSense version 2.4.3 or later.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:C");
      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:"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:"2017/09/19");
      script_set_attribute(attribute:"patch_publication_date", value:"2017/11/21");
      script_set_attribute(attribute:"plugin_publication_date", value:"2018/04/13");
    
      script_set_attribute(attribute:"plugin_type", value:"remote");
      script_set_attribute(attribute:"cpe", value:"cpe:/a:pfsense:pfsense");
      script_set_attribute(attribute:"cpe", value:"cpe:/a:bsdperimeter:pfsense");
      script_set_attribute(attribute:"stig_severity", value:"I");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"Firewalls");
    
      script_copyright(english:"This script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("pfsense_detect.nbin");
      script_require_keys("Host/pfSense");
    
      exit(0);
    }
    
    include("vcf.inc");
    include("vcf_extras.inc");
    
    if (!get_kb_item("Host/pfSense")) audit(AUDIT_HOST_NOT, "pfSense");
    
    app_info = vcf::pfsense::get_app_info();
    constraints = [
      { "fixed_version" : "2.4.3" }
    ];
    
    vcf::pfsense::check_version_and_report(
      app_info:app_info,
      constraints:constraints,
      severity:SECURITY_HOLE,
      flags:{xss:TRUE, xsrf:TRUE}
    );