Vulnerabilities > CVE-2014-8476 - Information Exposure vulnerability in Freebsd

047910
CVSS 2.1 - LOW
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
NONE
Availability impact
NONE
local
low complexity
freebsd
CWE-200
nessus

Summary

The setlogin function in FreeBSD 8.4 through 10.1-RC4 does not initialize the buffer used to store the login name, which allows local users to obtain sensitive information from kernel memory via a call to getlogin, which returns the entire buffer.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Subverting Environment Variable Values
    The attacker directly or indirectly modifies environment variables used by or controlling the target software. The attacker's goal is to cause the target software to deviate from its expected operation in a manner that benefits the attacker.
  • Footprinting
    An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
  • 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.
  • Browser Fingerprinting
    An attacker carefully crafts small snippets of Java Script to efficiently detect the type of browser the potential victim is using. Many web-based attacks need prior knowledge of the web browser including the version of browser to ensure successful exploitation of a vulnerability. Having this knowledge allows an attacker to target the victim with attacks that specifically exploit known or zero day weaknesses in the type and version of the browser used by the victim. Automating this process via Java Script as a part of the same delivery system used to exploit the browser is considered more efficient as the attacker can supply a browser fingerprinting method and integrate it with exploit code, all contained in Java Script and in response to the same web page request by the browser.
  • Session Credential Falsification through Prediction
    This attack targets predictable session ID in order to gain privileges. The attacker can predict the session ID used during a transaction to perform spoofing and session hijacking.

Nessus

  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_74389F22600711E6A6C314DAE9D210B8.NASL
    descriptionWhen setlogin(2) is called while setting up a new login session, the login name is copied into an uninitialized stack buffer, which is then copied into a buffer of the same size in the session structure. The getlogin(2) system call returns the entire buffer rather than just the portion occupied by the login name associated with the session. Impact : An unprivileged user can access this memory by calling getlogin(2) and reading beyond the terminating NUL character of the resulting string. Up to 16 (FreeBSD 8) or 32 (FreeBSD 9 and 10) bytes of kernel memory may be leaked in this manner for each invocation of setlogin(2). This memory may contain sensitive information, such as portions of the file cache or terminal buffers, which an attacker might leverage to obtain elevated privileges.
    last seen2020-06-01
    modified2020-06-02
    plugin id92912
    published2016-08-12
    reporterThis script is Copyright (C) 2016-2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/92912
    titleFreeBSD : FreeBSD -- Kernel stack disclosure in setlogin(2) / getlogin(2) (74389f22-6007-11e6-a6c3-14dae9d210b8)
    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(92912);
      script_version("2.3");
      script_cvs_date("Date: 2018/12/07  9:46:53");
    
      script_cve_id("CVE-2014-8476");
      script_bugtraq_id(70912);
      script_xref(name:"FreeBSD", value:"SA-14:25.setlogin");
    
      script_name(english:"FreeBSD : FreeBSD -- Kernel stack disclosure in setlogin(2) / getlogin(2) (74389f22-6007-11e6-a6c3-14dae9d210b8)");
      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:
    "When setlogin(2) is called while setting up a new login session, the
    login name is copied into an uninitialized stack buffer, which is then
    copied into a buffer of the same size in the session structure. The
    getlogin(2) system call returns the entire buffer rather than just the
    portion occupied by the login name associated with the session. Impact
    : An unprivileged user can access this memory by calling getlogin(2)
    and reading beyond the terminating NUL character of the resulting
    string. Up to 16 (FreeBSD 8) or 32 (FreeBSD 9 and 10) bytes of kernel
    memory may be leaked in this manner for each invocation of
    setlogin(2).
    
    This memory may contain sensitive information, such as portions of the
    file cache or terminal buffers, which an attacker might leverage to
    obtain elevated privileges."
      );
      # https://vuxml.freebsd.org/freebsd/74389f22-6007-11e6-a6c3-14dae9d210b8.html
      script_set_attribute(
        attribute:"see_also",
        value:"http://www.nessus.org/u?0d6a52f8"
      );
      script_set_attribute(attribute:"solution", value:"Update the affected packages.");
      script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:P/I:N/A:N");
      script_set_cvss_temporal_vector("CVSS2#E:ND/RL:OF/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:freebsd:freebsd:FreeBSD");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2014/11/04");
      script_set_attribute(attribute:"patch_publication_date", value:"2016/08/11");
      script_set_attribute(attribute:"plugin_publication_date", value:"2016/08/12");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2016-2018 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>=10.0<10.0_12")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=9.3<9.3_5")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=9.2<9.2_15")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=9.1<9.1_22")) flag++;
    if (pkg_test(save_report:TRUE, pkg:"FreeBSD>=8.4<8.4_19")) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_note(port:0, extra:pkg_report_get());
      else security_note(0);
      exit(0);
    }
    else audit(AUDIT_HOST_NOT, "affected");
    
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-3070.NASL
    descriptionSeveral vulnerabilities have been discovered in the FreeBSD kernel that may lead to a denial of service or information disclosure. - CVE-2014-3711 Denial of service through memory leak in sandboxed namei lookups. - CVE-2014-3952 Kernel memory disclosure in sockbuf control messages. - CVE-2014-3953 Kernel memory disclosure in SCTP. This update disables SCTP, since the userspace tools shipped in Wheezy didn
    last seen2020-03-17
    modified2014-11-10
    plugin id79066
    published2014-11-10
    reporterThis script is Copyright (C) 2014-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/79066
    titleDebian DSA-3070-1 : kfreebsd-9 - security update