Vulnerabilities > CVE-2019-11481 - Link Following vulnerability in multiple products

047910
CVSS 7.8 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
local
low complexity
canonical
apport-project
CWE-59
nessus

Summary

Kevin Backhouse discovered that apport would read a user-supplied configuration file with elevated privileges. By replacing the file with a symbolic link, a user could get apport to read any file on the system as root, with unknown consequences.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Symlink Attack
    An attacker positions a symbolic link in such a manner that the targeted user or application accesses the link's endpoint, assuming that it is accessing a file with the link's name. The endpoint file may be either output or input. If the file is output, the result is that the endpoint is modified, instead of a file at the intended location. Modifications to the endpoint file may include appending, overwriting, corrupting, changing permissions, or other modifications. In some variants of this attack the attacker may be able to control the change to a file while in other cases they cannot. The former is especially damaging since the attacker may be able to grant themselves increased privileges or insert false information, but the latter can also be damaging as it can expose sensitive information or corrupt or destroy vital system or application files. Alternatively, the endpoint file may serve as input to the targeted application. This can be used to feed malformed input into the target or to cause the target to process different information, possibly allowing the attacker to control the actions of the target or to cause the target to expose information to the attacker. Moreover, the actions taken on the endpoint file are undertaken with the permissions of the targeted user or application, which may exceed the permissions that the attacker would normally have.
  • Accessing, Modifying or Executing Executable Files
    An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
  • Leverage Executable Code in Non-Executable Files
    An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high. The attack can be directed at a client system, such as causing buffer overrun through loading seemingly benign image files, as in Microsoft Security Bulletin MS04-028 where specially crafted JPEG files could cause a buffer overrun once loaded into the browser. Another example targets clients reading pdf files. In this case the attacker simply appends javascript to the end of a legitimate url for a pdf (http://www.gnucitizen.org/blog/danger-danger-danger/) http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_here The client assumes that they are reading a pdf, but the attacker has modified the resource and loaded executable javascript into the client's browser process. The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality. The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.

Nessus

  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4171-1.NASL
    descriptionKevin Backhouse discovered Apport would read its user-controlled settings file as the root user. This could be used by a local attacker to possibly crash Apport or have other unspecified consequences. (CVE-2019-11481) Sander Bos discovered a race-condition in Apport during core dump creation. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11482) Sander Bos discovered Apport mishandled crash dumps originating from containers. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11483) Sander Bos discovered Apport mishandled lock-file creation. This could be used by a local attacker to cause a denial of service against Apport. (CVE-2019-11485) Kevin Backhouse discovered Apport read various process-specific files with elevated privileges during crash dump generation. This could could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-15790). 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 id130396
    published2019-10-30
    reporterUbuntu Security Notice (C) 2019-2020 Canonical, Inc. / NASL script (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/130396
    titleUbuntu 16.04 LTS / 18.04 LTS / 19.04 / 19.10 : apport vulnerabilities (USN-4171-1)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Ubuntu Security Notice USN-4171-1. 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(130396);
      script_version("1.4");
      script_cvs_date("Date: 2020/02/14");
    
      script_cve_id("CVE-2019-11481", "CVE-2019-11482", "CVE-2019-11483", "CVE-2019-11485", "CVE-2019-15790");
      script_xref(name:"USN", value:"4171-1");
    
      script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS / 19.04 / 19.10 : apport vulnerabilities (USN-4171-1)");
      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:
    "Kevin Backhouse discovered Apport would read its user-controlled
    settings file as the root user. This could be used by a local attacker
    to possibly crash Apport or have other unspecified consequences.
    (CVE-2019-11481)
    
    Sander Bos discovered a race-condition in Apport during core dump
    creation. This could be used by a local attacker to generate a crash
    report for a privileged process that is readable by an unprivileged
    user. (CVE-2019-11482)
    
    Sander Bos discovered Apport mishandled crash dumps originating from
    containers. This could be used by a local attacker to generate a crash
    report for a privileged process that is readable by an unprivileged
    user. (CVE-2019-11483)
    
    Sander Bos discovered Apport mishandled lock-file creation. This could
    be used by a local attacker to cause a denial of service against
    Apport. (CVE-2019-11485)
    
    Kevin Backhouse discovered Apport read various process-specific files
    with elevated privileges during crash dump generation. This could
    could be used by a local attacker to generate a crash report for a
    privileged process that is readable by an unprivileged user.
    (CVE-2019-15790).
    
    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/4171-1/"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "Update the affected apport, python-apport and / or python3-apport
    packages."
      );
      script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/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:L/AC:L/PR:L/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:"cvss_score_source", value:"CVE-2019-11481");
      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:apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-apport");
      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:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.04");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/08");
      script_set_attribute(attribute:"patch_publication_date", value:"2019/10/30");
      script_set_attribute(attribute:"plugin_publication_date", value:"2019/10/30");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"Ubuntu Security Notice (C) 2019-2020 Canonical, Inc. / NASL script (C) 2019-2020 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:"^(16\.04|18\.04|19\.04|19\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04 / 18.04 / 19.04 / 19.10", "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:"apport", pkgver:"2.20.1-0ubuntu2.20")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python-apport", pkgver:"2.20.1-0ubuntu2.20")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python3-apport", pkgver:"2.20.1-0ubuntu2.20")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"apport", pkgver:"2.20.9-0ubuntu7.8")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python-apport", pkgver:"2.20.9-0ubuntu7.8")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python3-apport", pkgver:"2.20.9-0ubuntu7.8")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"apport", pkgver:"2.20.10-0ubuntu27.2")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"python-apport", pkgver:"2.20.10-0ubuntu27.2")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"python3-apport", pkgver:"2.20.10-0ubuntu27.2")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"apport", pkgver:"2.20.11-0ubuntu8.1")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python-apport", pkgver:"2.20.11-0ubuntu8.1")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python3-apport", pkgver:"2.20.11-0ubuntu8.1")) 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, "apport / python-apport / python3-apport");
    }
    
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4171-3.NASL
    descriptionUSN-4171-1 fixed vulnerabilities in Apport. The update caused a regression in the Python Apport library. This update fixes the problem. We apologize for the inconvenience. Original advisory details : Kevin Backhouse discovered Apport would read its user-controlled settings file as the root user. This could be used by a local attacker to possibly crash Apport or have other unspecified consequences. (CVE-2019-11481) Sander Bos discovered a race-condition in Apport during core dump creation. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11482) Sander Bos discovered Apport mishandled crash dumps originating from containers. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11483) Sander Bos discovered Apport mishandled lock-file creation. This could be used by a local attacker to cause a denial of service against Apport. (CVE-2019-11485) Kevin Backhouse discovered Apport read various process-specific files with elevated privileges during crash dump generation. This could could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-15790). 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 id130586
    published2019-11-06
    reporterUbuntu Security Notice (C) 2019-2020 Canonical, Inc. / NASL script (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/130586
    titleUbuntu 16.04 LTS / 18.04 LTS / 19.04 / 19.10 : apport regression (USN-4171-3)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Ubuntu Security Notice USN-4171-3. 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(130586);
      script_version("1.4");
      script_cvs_date("Date: 2020/02/14");
    
      script_cve_id("CVE-2019-11481", "CVE-2019-11482", "CVE-2019-11483", "CVE-2019-11485", "CVE-2019-15790");
      script_xref(name:"USN", value:"4171-3");
    
      script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS / 19.04 / 19.10 : apport regression (USN-4171-3)");
      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:
    "USN-4171-1 fixed vulnerabilities in Apport. The update caused a
    regression in the Python Apport library. This update fixes the
    problem.
    
    We apologize for the inconvenience.
    
    Original advisory details :
    
    Kevin Backhouse discovered Apport would read its user-controlled
    settings file as the root user. This could be used by a local attacker
    to possibly crash Apport or have other unspecified consequences.
    (CVE-2019-11481)
    
    Sander Bos discovered a race-condition in Apport during core
    dump creation. This could be used by a local attacker to
    generate a crash report for a privileged process that is
    readable by an unprivileged user. (CVE-2019-11482)
    
    Sander Bos discovered Apport mishandled crash dumps
    originating from containers. This could be used by a local
    attacker to generate a crash report for a privileged process
    that is readable by an unprivileged user. (CVE-2019-11483)
    
    Sander Bos discovered Apport mishandled lock-file creation.
    This could be used by a local attacker to cause a denial of
    service against Apport. (CVE-2019-11485)
    
    Kevin Backhouse discovered Apport read various
    process-specific files with elevated privileges during crash
    dump generation. This could could be used by a local
    attacker to generate a crash report for a privileged process
    that is readable by an unprivileged user. (CVE-2019-15790).
    
    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/4171-3/"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "Update the affected apport, python-apport and / or python3-apport
    packages."
      );
      script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/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:L/AC:L/PR:L/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:"cvss_score_source", value:"CVE-2019-11481");
      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:apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-apport");
      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:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.04");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/08");
      script_set_attribute(attribute:"patch_publication_date", value:"2019/11/05");
      script_set_attribute(attribute:"plugin_publication_date", value:"2019/11/06");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"Ubuntu Security Notice (C) 2019-2020 Canonical, Inc. / NASL script (C) 2019-2020 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:"^(16\.04|18\.04|19\.04|19\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04 / 18.04 / 19.04 / 19.10", "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:"apport", pkgver:"2.20.1-0ubuntu2.21")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python-apport", pkgver:"2.20.1-0ubuntu2.21")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python3-apport", pkgver:"2.20.1-0ubuntu2.21")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"apport", pkgver:"2.20.9-0ubuntu7.9")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python-apport", pkgver:"2.20.9-0ubuntu7.9")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python3-apport", pkgver:"2.20.9-0ubuntu7.9")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"apport", pkgver:"2.20.10-0ubuntu27.3")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"python-apport", pkgver:"2.20.10-0ubuntu27.3")) flag++;
    if (ubuntu_check(osver:"19.04", pkgname:"python3-apport", pkgver:"2.20.10-0ubuntu27.3")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"apport", pkgver:"2.20.11-0ubuntu8.2")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python-apport", pkgver:"2.20.11-0ubuntu8.2")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python3-apport", pkgver:"2.20.11-0ubuntu8.2")) 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, "apport / python-apport / python3-apport");
    }
    
  • NASL familyUbuntu Local Security Checks
    NASL idUBUNTU_USN-4171-5.NASL
    descriptionUSN-4171-1 fixed vulnerabilities in Apport. This caused a regression in autopkgtest and python2 compatibility. This update fixes the problem. We apologize for the inconvenience. Original advisory details : Kevin Backhouse discovered Apport would read its user-controlled settings file as the root user. This could be used by a local attacker to possibly crash Apport or have other unspecified consequences. (CVE-2019-11481) Sander Bos discovered a race-condition in Apport during core dump creation. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11482) Sander Bos discovered Apport mishandled crash dumps originating from containers. This could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-11483) Sander Bos discovered Apport mishandled lock-file creation. This could be used by a local attacker to cause a denial of service against Apport. (CVE-2019-11485) Kevin Backhouse discovered Apport read various process-specific files with elevated privileges during crash dump generation. This could could be used by a local attacker to generate a crash report for a privileged process that is readable by an unprivileged user. (CVE-2019-15790). 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 seen2020-03-21
    modified2020-03-18
    plugin id134657
    published2020-03-18
    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/134657
    titleUbuntu 16.04 LTS / 18.04 LTS / 19.10 : apport regression (USN-4171-5)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Ubuntu Security Notice USN-4171-5. 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(134657);
      script_version("1.2");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/03/20");
    
      script_cve_id("CVE-2019-11481", "CVE-2019-11482", "CVE-2019-11483", "CVE-2019-11485", "CVE-2019-15790");
      script_xref(name:"USN", value:"4171-5");
    
      script_name(english:"Ubuntu 16.04 LTS / 18.04 LTS / 19.10 : apport regression (USN-4171-5)");
      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:
    "USN-4171-1 fixed vulnerabilities in Apport. This caused a regression
    in autopkgtest and python2 compatibility. This update fixes the
    problem.
    
    We apologize for the inconvenience.
    
    Original advisory details :
    
    Kevin Backhouse discovered Apport would read its user-controlled
    settings file as the root user. This could be used by a local attacker
    to possibly crash Apport or have other unspecified consequences.
    (CVE-2019-11481)
    
    Sander Bos discovered a race-condition in Apport during core
    dump creation. This could be used by a local attacker to
    generate a crash report for a privileged process that is
    readable by an unprivileged user. (CVE-2019-11482)
    
    Sander Bos discovered Apport mishandled crash dumps
    originating from containers. This could be used by a local
    attacker to generate a crash report for a privileged process
    that is readable by an unprivileged user. (CVE-2019-11483)
    
    Sander Bos discovered Apport mishandled lock-file creation.
    This could be used by a local attacker to cause a denial of
    service against Apport. (CVE-2019-11485)
    
    Kevin Backhouse discovered Apport read various
    process-specific files with elevated privileges during crash
    dump generation. This could could be used by a local
    attacker to generate a crash report for a privileged process
    that is readable by an unprivileged user. (CVE-2019-15790).
    
    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/4171-5/"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "Update the affected apport, python-apport and / or python3-apport
    packages."
      );
      script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/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:L/AC:L/PR:L/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python-apport");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:python3-apport");
      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:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2020/02/08");
      script_set_attribute(attribute:"patch_publication_date", value:"2020/03/18");
      script_set_attribute(attribute:"plugin_publication_date", value:"2020/03/18");
      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:"^(16\.04|18\.04|19\.10)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 16.04 / 18.04 / 19.10", "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:"apport", pkgver:"2.20.1-0ubuntu2.22")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python-apport", pkgver:"2.20.1-0ubuntu2.22")) flag++;
    if (ubuntu_check(osver:"16.04", pkgname:"python3-apport", pkgver:"2.20.1-0ubuntu2.22")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"apport", pkgver:"2.20.9-0ubuntu7.12")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python-apport", pkgver:"2.20.9-0ubuntu7.12")) flag++;
    if (ubuntu_check(osver:"18.04", pkgname:"python3-apport", pkgver:"2.20.9-0ubuntu7.12")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"apport", pkgver:"2.20.11-0ubuntu8.6")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python-apport", pkgver:"2.20.11-0ubuntu8.6")) flag++;
    if (ubuntu_check(osver:"19.10", pkgname:"python3-apport", pkgver:"2.20.11-0ubuntu8.6")) 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, "apport / python-apport / python3-apport");
    }