Vulnerabilities > CVE-2019-13115 - Integer Overflow or Wraparound vulnerability in multiple products

047910
CVSS 8.1 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
HIGH

Summary

In libssh2 before 1.9.0, kex_method_diffie_hellman_group_exchange_sha256_key_exchange in kex.c has an integer overflow that could lead to an out-of-bounds read in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to disclose sensitive information or cause a denial of service condition on the client system when a user connects to the server. This is related to an _libssh2_check_length mistake, and is different from the various issues fixed in 1.8.1, such as CVE-2019-3855.

Vulnerable Configurations

Part Description Count
Application
Libssh2
35
Application
Netapp
17
Application
F5
2
OS
Debian
2
OS
Fedoraproject
2

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Forced Integer Overflow
    This attack forces an integer variable to go out of range. The integer variable is often used as an offset such as size of memory allocation or similarly. The attacker would typically control the value of such variable and try to get it out of range. For instance the integer in question is incremented past the maximum possible value, it may wrap to become a very small, or negative number, therefore providing a very incorrect value which can lead to unexpected behavior. At worst the attacker can execute arbitrary code.

Nessus

  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2019-9D85600FC7.NASL
    descriptionA vulnerability was discovered in libssh2 before 1.9.0, `kex_method_diffie_hellman_group_exchange_sha256_key_exchange` in `kex.c` has an integer overflow that could lead to an out-of-bounds write in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server. This is related to an `_libssh2_check_length` mistake, and is different from the various issues fixed in 1.8.1, such as CVE-2019-3855. This update, to the latest current upstream release 1.9.0, addresses this security issue and also includes a number of other bug fixes and enhancements as described in the package changelog. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. 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 id127521
    published2019-08-12
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/127521
    titleFedora 30 : libssh2 (2019-9d85600fc7)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from Fedora Security Advisory FEDORA-2019-9d85600fc7.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(127521);
      script_version("1.3");
      script_cvs_date("Date: 2020/01/06");
    
      script_cve_id("CVE-2019-13115", "CVE-2019-3855");
      script_xref(name:"FEDORA", value:"2019-9d85600fc7");
    
      script_name(english:"Fedora 30 : libssh2 (2019-9d85600fc7)");
      script_summary(english:"Checks rpm output for the updated package.");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:"The remote Fedora host is missing a security update."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "A vulnerability was discovered in libssh2 before 1.9.0,
    `kex_method_diffie_hellman_group_exchange_sha256_key_exchange` in
    `kex.c` has an integer overflow that could lead to an out-of-bounds
    write in the way packets are read from the server. A remote attacker
    who compromises a SSH server may be able to execute code on the client
    system when a user connects to the server.
    
    This is related to an `_libssh2_check_length` mistake, and is
    different from the various issues fixed in 1.8.1, such as
    CVE-2019-3855.
    
    This update, to the latest current upstream release 1.9.0, addresses
    this security issue and also includes a number of other bug fixes and
    enhancements as described in the package changelog.
    
    Note that Tenable Network Security has extracted the preceding
    description block directly from the Fedora update system website.
    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://bodhi.fedoraproject.org/updates/FEDORA-2019-9d85600fc7"
      );
      script_set_attribute(
        attribute:"solution", 
        value:"Update the affected libssh2 package."
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:C/I:C/A:C");
      script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:R/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:fedoraproject:fedora:libssh2");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:30");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2019/03/21");
      script_set_attribute(attribute:"patch_publication_date", value:"2019/08/02");
      script_set_attribute(attribute:"plugin_publication_date", value:"2019/08/12");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"Fedora Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/RedHat/release", "Host/RedHat/rpm-list");
    
      exit(0);
    }
    
    
    include("audit.inc");
    include("global_settings.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) || "Fedora" >!< release) audit(AUDIT_OS_NOT, "Fedora");
    os_ver = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
    if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
    os_ver = os_ver[1];
    if (! preg(pattern:"^30([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 30", "Fedora " + 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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "Fedora", cpu);
    
    
    flag = 0;
    if (rpm_check(release:"FC30", reference:"libssh2-1.9.0-1.fc30")) flag++;
    
    
    if (flag)
    {
      security_report_v4(
        port       : 0,
        severity   : SECURITY_HOLE,
        extra      : rpm_report_get()
      );
      exit(0);
    }
    else
    {
      tested = pkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libssh2");
    }
    
  • NASL familyPhotonOS Local Security Checks
    NASL idPHOTONOS_PHSA-2019-3_0-0026_LIBSSH2.NASL
    descriptionAn update of the libssh2 package has been released.
    last seen2020-06-01
    modified2020-06-02
    plugin id129102
    published2019-09-23
    reporterThis script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/129102
    titlePhoton OS 3.0: Libssh2 PHSA-2019-3.0-0026
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    
    
    # The descriptive text and package checks in this plugin were
    # extracted from VMware Security Advisory PHSA-2019-3.0-0026. The text
    # itself is copyright (C) VMware, Inc.
    
    
    include('compat.inc');
    
    if (description)
    {
      script_id(129102);
      script_version("1.2");
      script_cvs_date("Date: 2019/12/24");
    
      script_cve_id("CVE-2019-13115");
    
      script_name(english:"Photon OS 3.0: Libssh2 PHSA-2019-3.0-0026");
    
      script_set_attribute(attribute:"synopsis", value:
    "The remote PhotonOS host is missing multiple security updates.");
      script_set_attribute(attribute:"description", value:
    "An update of the libssh2 package has been released.");
      script_set_attribute(attribute:"see_also", value:"https://github.com/vmware/photon/wiki/Security-Updates-3.0-0026.md");
      script_set_attribute(attribute:"solution", value:
    "Update the affected Linux packages.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:P/I:N/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:L/PR:N/UI:R/S:U/C:H/I:N/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-2019-13115");
    
      script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2019/07/16");
      script_set_attribute(attribute:"patch_publication_date", value:"2019/08/21");
      script_set_attribute(attribute:"plugin_publication_date", value:"2019/09/23");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:vmware:photonos:libssh2");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:vmware:photonos:3.0");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_family(english:"PhotonOS Local Security Checks");
    
      script_copyright(english:"This script is Copyright (C) 2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/PhotonOS/release", "Host/PhotonOS/rpm-list");
    
      exit(0);
    }
    
    include("audit.inc");
    include("global_settings.inc");
    include("rpm.inc");
    
    if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
    
    release = get_kb_item("Host/PhotonOS/release");
    if (isnull(release) || release !~ "^VMware Photon") audit(AUDIT_OS_NOT, "PhotonOS");
    if (release !~ "^VMware Photon (?:Linux|OS) 3\.0(\D|$)") audit(AUDIT_OS_NOT, "PhotonOS 3.0");
    
    if (!get_kb_item("Host/PhotonOS/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$") audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "PhotonOS", cpu);
    
    flag = 0;
    
    if (rpm_check(release:"PhotonOS-3.0", reference:"libssh2-1.9.0-1.ph3")) flag++;
    if (rpm_check(release:"PhotonOS-3.0", reference:"libssh2-debuginfo-1.9.0-1.ph3")) flag++;
    if (rpm_check(release:"PhotonOS-3.0", reference:"libssh2-devel-1.9.0-1.ph3")) flag++;
    
    if (flag)
    {
      security_report_v4(
        port       : 0,
        severity   : SECURITY_WARNING,
        extra      : rpm_report_get()
      );
      exit(0);
    }
    else
    {
      tested = pkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libssh2");
    }
    
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2019-5885663621.NASL
    descriptionA vulnerability was discovered in libssh2 before 1.9.0, `kex_method_diffie_hellman_group_exchange_sha256_key_exchange` in `kex.c` has an integer overflow that could lead to an out-of-bounds write in the way packets are read from the server. A remote attacker who compromises a SSH server may be able to execute code on the client system when a user connects to the server. This is related to an `_libssh2_check_length` mistake, and is different from the various issues fixed in 1.8.1, such as CVE-2019-3855. This update, to the latest current upstream release 1.9.0, addresses this security issue and also includes a number of other bug fixes and enhancements as described in the package changelog. Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. 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 id127512
    published2019-08-12
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/127512
    titleFedora 29 : libssh2 (2019-5885663621)