Vulnerabilities > CVE-2017-6542 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in multiple products

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
putty
opensuse-project
opensuse
CWE-119
critical
nessus
exploit available

Summary

The ssh_agent_channel_data function in PuTTY before 0.68 allows remote attackers to have unspecified impact via a large length value in an agent protocol message and leveraging the ability to connect to the Unix-domain socket representing the forwarded agent connection, which trigger a buffer overflow.

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Buffer Overflow via Environment Variables
    This attack pattern involves causing a buffer overflow through manipulation of environment variables. Once the attacker finds that they can modify an environment variable, they may try to overflow associated buffers. This attack leverages implicit trust often placed in environment variables.
  • Overflow Buffers
    Buffer Overflow attacks target improper or missing bounds checking on buffer operations, typically triggered by input injected by an attacker. As a consequence, an attacker is able to write past the boundaries of allocated buffer regions in memory, causing a program crash or potentially redirection of execution as per the attackers' choice.
  • Client-side Injection-induced Buffer Overflow
    This type of attack exploits a buffer overflow vulnerability in targeted client software through injection of malicious content from a custom-built hostile service.
  • Filter Failure through Buffer Overflow
    In this attack, the idea is to cause an active filter to fail by causing an oversized transaction. An attacker may try to feed overly long input strings to the program in an attempt to overwhelm the filter (by causing a buffer overflow) and hoping that the filter does not fail securely (i.e. the user input is let into the system unfiltered).
  • MIME Conversion
    An attacker exploits a weakness in the MIME conversion routine to cause a buffer overflow and gain control over the mail server machine. The MIME system is designed to allow various different information formats to be interpreted and sent via e-mail. Attack points exist when data are converted to MIME compatible format and back.

Exploit-Db

descriptionPuTTY < 0.68 - 'ssh_agent_channel_data' Integer Overflow Heap Corruption. CVE-2017-6542. Dos exploit for Linux platform. Tags: Integer Overflow
fileexploits/linux/dos/42137.txt
idEDB-ID:42137
last seen2017-06-07
modified2017-06-07
platformlinux
port22
published2017-06-07
reporterExploit-DB
sourcehttps://www.exploit-db.com/download/42137/
titlePuTTY < 0.68 - 'ssh_agent_channel_data' Integer Overflow Heap Corruption
typedos

Nessus

  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_9B973E970A9911E7ACE7080027EF73EC.NASL
    descriptionSimon G. Tatham reports : Many versions of PuTTY prior to 0.68 have a heap-corrupting integer overflow bug in the ssh_agent_channel_data function which processes messages sent by remote SSH clients to a forwarded agent connection. [...] This bug is only exploitable at all if you have enabled SSH agent forwarding, which is turned off by default. Moreover, an attacker able to exploit this bug would have to have already be able to connect to the Unix-domain socket representing the forwarded agent connection. Since any attacker with that capability would necessarily already be able to generate signatures with your agent
    last seen2020-06-01
    modified2020-06-02
    plugin id97789
    published2017-03-17
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/97789
    titleFreeBSD : PuTTY -- integer overflow permits memory overwrite by forwarded ssh-agent connections (9b973e97-0a99-11e7-ace7-080027ef73ec)
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from the FreeBSD VuXML database :
    #
    # Copyright 2003-2019 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(97789);
      script_version("3.7");
      script_cvs_date("Date: 2019/07/10 16:04:13");
    
      script_cve_id("CVE-2017-6542");
    
      script_name(english:"FreeBSD : PuTTY -- integer overflow permits memory overwrite by forwarded ssh-agent connections (9b973e97-0a99-11e7-ace7-080027ef73ec)");
      script_summary(english:"Checks for updated package in pkg_info output");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:"The remote FreeBSD host is missing a security-related update."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "Simon G. Tatham reports :
    
    Many versions of PuTTY prior to 0.68 have a heap-corrupting integer
    overflow bug in the ssh_agent_channel_data function which processes
    messages sent by remote SSH clients to a forwarded agent connection.
    [...]
    
    This bug is only exploitable at all if you have enabled SSH agent
    forwarding, which is turned off by default. Moreover, an attacker able
    to exploit this bug would have to have already be able to connect to
    the Unix-domain socket representing the forwarded agent connection.
    Since any attacker with that capability would necessarily already be
    able to generate signatures with your agent's stored private keys, you
    should in normal circumstances be defended against this vulnerability
    by the same precautions you and your operating system were already
    taking to prevent untrusted people from accessing your SSH agent."
      );
      # http://www.chiark.greenend.org.uk/~sgtatham/putty/wishlist/vuln-agent-fwd-overflow.html
      script_set_attribute(
        attribute:"see_also",
        value:"http://www.nessus.org/u?e85f1139"
      );
      # https://vuxml.freebsd.org/freebsd/9b973e97-0a99-11e7-ace7-080027ef73ec.html
      script_set_attribute(
        attribute:"see_also",
        value:"http://www.nessus.org/u?c36fdac1"
      );
      script_set_attribute(attribute:"solution", value:"Update the affected package.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
      script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:putty");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2017/01/29");
      script_set_attribute(attribute:"patch_publication_date", value:"2017/03/16");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/17");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017-2019 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");
    
      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);
    
    
    flag = 0;
    
    if (pkg_test(save_report:TRUE, pkg:"putty<0.68")) 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 familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201706-09.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201706-09 (FileZilla: Buffer overflow) FileZilla is affected by the same vulnerability as reported in &ldquo;GLSA 201703-03&rdquo; because the package included a vulnerable copy of PuTTY. Please read the GLSA for PuTTY referenced below for details. Impact : A remote attacker, utilizing the SSH agent forwarding of an SSH server, could execute arbitrary code with the privileges of the user running FileZilla or cause a Denial of Service condition. Workaround : There is no known workaround at this time.
    last seen2020-06-01
    modified2020-06-02
    plugin id100652
    published2017-06-07
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/100652
    titleGLSA-201706-09 : FileZilla: Buffer overflow
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Gentoo Linux Security Advisory GLSA 201706-09.
    #
    # The advisory text is Copyright (C) 2001-2018 Gentoo Foundation, Inc.
    # and licensed under the Creative Commons - Attribution / Share Alike 
    # license. See http://creativecommons.org/licenses/by-sa/3.0/
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(100652);
      script_version("3.3");
      script_cvs_date("Date: 2019/04/10 16:10:17");
    
      script_cve_id("CVE-2017-6542");
      script_xref(name:"GLSA", value:"201706-09");
    
      script_name(english:"GLSA-201706-09 : FileZilla: Buffer overflow");
      script_summary(english:"Checks for updated package(s) in /var/db/pkg");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:
    "The remote Gentoo host is missing one or more security-related
    patches."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "The remote host is affected by the vulnerability described in GLSA-201706-09
    (FileZilla: Buffer overflow)
    
        FileZilla is affected by the same vulnerability as reported in &ldquo;GLSA
          201703-03&rdquo; because the package included a vulnerable copy of PuTTY.
          Please read the GLSA for PuTTY referenced below for details.
      
    Impact :
    
        A remote attacker, utilizing the SSH agent forwarding of an SSH server,
          could execute arbitrary code with the privileges of the user running
          FileZilla or cause a Denial of Service condition.
      
    Workaround :
    
        There is no known workaround at this time."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security.gentoo.org/glsa/201703-03"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security.gentoo.org/glsa/201706-09"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "All FileZilla users should upgrade to the latest version:
          # emerge --sync
          # emerge --ask --oneshot --verbose '>=net-ftp/filezilla-3.25.2'"
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
      script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:filezilla");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2017/06/06");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/06/07");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"Gentoo Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");
    
      exit(0);
    }
    
    
    include("audit.inc");
    include("global_settings.inc");
    include("qpkg.inc");
    
    if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
    if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
    if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
    
    
    flag = 0;
    
    if (qpkg_check(package:"net-ftp/filezilla", unaffected:make_list("ge 3.25.2"), vulnerable:make_list("lt 3.25.2"))) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_hole(port:0, extra:qpkg_report_get());
      else security_hole(0);
      exit(0);
    }
    else
    {
      tested = qpkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "FileZilla");
    }
    
  • NASL familySuSE Local Security Checks
    NASL idOPENSUSE-2017-354.NASL
    descriptionThis update to putty 0.68 fixes the following security issue : - CVE-2017-6542: If SSH agent forwarding is enabled, local attackers that are also able to connect to the UNIX domain socket could have overwritten heap data (boo#1029256)
    last seen2020-06-05
    modified2017-03-20
    plugin id97818
    published2017-03-20
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/97818
    titleopenSUSE Security Update : putty (openSUSE-2017-354)
    code
    #%NASL_MIN_LEVEL 80502
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from openSUSE Security Update openSUSE-2017-354.
    #
    # The text description of this plugin is (C) SUSE LLC.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(97818);
      script_version("3.5");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");
    
      script_cve_id("CVE-2017-6542");
    
      script_name(english:"openSUSE Security Update : putty (openSUSE-2017-354)");
      script_summary(english:"Check for the openSUSE-2017-354 patch");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:"The remote openSUSE host is missing a security update."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "This update to putty 0.68 fixes the following security issue :
    
      - CVE-2017-6542: If SSH agent forwarding is enabled, local
        attackers that are also able to connect to the UNIX
        domain socket could have overwritten heap data
        (boo#1029256)"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://bugzilla.opensuse.org/show_bug.cgi?id=1029256"
      );
      script_set_attribute(
        attribute:"solution", 
        value:"Update the affected putty packages."
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
      script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:putty");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:putty-debuginfo");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:novell:opensuse:putty-debugsource");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:42.1");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:novell:opensuse:42.2");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2017/03/19");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/20");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"SuSE Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/SuSE/release", "Host/SuSE/rpm-list", "Host/cpu");
    
      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/SuSE/release");
    if (isnull(release) || release =~ "^(SLED|SLES)") audit(AUDIT_OS_NOT, "openSUSE");
    if (release !~ "^(SUSE42\.1|SUSE42\.2)$") audit(AUDIT_OS_RELEASE_NOT, "openSUSE", "42.1 / 42.2", release);
    if (!get_kb_item("Host/SuSE/rpm-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
    
    ourarch = get_kb_item("Host/cpu");
    if (!ourarch) audit(AUDIT_UNKNOWN_ARCH);
    if (ourarch !~ "^(i586|i686|x86_64)$") audit(AUDIT_ARCH_NOT, "i586 / i686 / x86_64", ourarch);
    
    flag = 0;
    
    if ( rpm_check(release:"SUSE42.1", reference:"putty-0.68-12.1") ) flag++;
    if ( rpm_check(release:"SUSE42.1", reference:"putty-debuginfo-0.68-12.1") ) flag++;
    if ( rpm_check(release:"SUSE42.1", reference:"putty-debugsource-0.68-12.1") ) flag++;
    if ( rpm_check(release:"SUSE42.2", reference:"putty-0.68-12.1") ) flag++;
    if ( rpm_check(release:"SUSE42.2", reference:"putty-debuginfo-0.68-12.1") ) flag++;
    if ( rpm_check(release:"SUSE42.2", reference:"putty-debugsource-0.68-12.1") ) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_hole(port:0, extra:rpm_report_get());
      else security_hole(0);
      exit(0);
    }
    else
    {
      tested = pkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "putty / putty-debuginfo / putty-debugsource");
    }
    
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-EFDD962FEE.NASL
    descriptionThis is an update fixing CVE-2017-6542. 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 seen2020-06-05
    modified2017-07-21
    plugin id101873
    published2017-07-21
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/101873
    titleFedora 25 : putty (2017-efdd962fee)
    code
    #%NASL_MIN_LEVEL 80502
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from Fedora Security Advisory FEDORA-2017-efdd962fee.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(101873);
      script_version("3.5");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");
    
      script_cve_id("CVE-2017-6542");
      script_xref(name:"FEDORA", value:"2017-efdd962fee");
    
      script_name(english:"Fedora 25 : putty (2017-efdd962fee)");
      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:
    "This is an update fixing CVE-2017-6542.
    
    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-2017-efdd962fee"
      );
      script_set_attribute(attribute:"solution", value:"Update the affected putty package.");
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
      script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:putty");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:25");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2017/03/27");
      script_set_attribute(attribute:"patch_publication_date", value:"2017/07/19");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/07/21");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017-2020 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:"^25([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 25", "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:"FC25", reference:"putty-0.70-1.fc25")) 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, "putty");
    }
    
  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201703-03.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201703-03 (PuTTY: Buffer overflow) A heap-corrupting buffer overflow bug in the ssh_agent_channel_data function of PuTTY was found. Impact : A remote attacker, utilizing the SSH agent forwarding of an SSH server, could execute arbitrary code with the privileges of the user running the client or cause a Denial of Service condition. Workaround : There is no known workaround at this time.
    last seen2020-06-01
    modified2020-06-02
    plugin id97815
    published2017-03-20
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/97815
    titleGLSA-201703-03 : PuTTY: Buffer overflow
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Gentoo Linux Security Advisory GLSA 201703-03.
    #
    # The advisory text is Copyright (C) 2001-2018 Gentoo Foundation, Inc.
    # and licensed under the Creative Commons - Attribution / Share Alike 
    # license. See http://creativecommons.org/licenses/by-sa/3.0/
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(97815);
      script_version("3.4");
      script_cvs_date("Date: 2019/04/10 16:10:17");
    
      script_cve_id("CVE-2017-6542");
      script_xref(name:"GLSA", value:"201703-03");
    
      script_name(english:"GLSA-201703-03 : PuTTY: Buffer overflow");
      script_summary(english:"Checks for updated package(s) in /var/db/pkg");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:
    "The remote Gentoo host is missing one or more security-related
    patches."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "The remote host is affected by the vulnerability described in GLSA-201703-03
    (PuTTY: Buffer overflow)
    
        A heap-corrupting buffer overflow bug in the ssh_agent_channel_data
          function of PuTTY was found.
      
    Impact :
    
        A remote attacker, utilizing the SSH agent forwarding of an SSH server,
          could execute arbitrary code with the privileges of the user running the
          client or cause a Denial of Service condition.
      
    Workaround :
    
        There is no known workaround at this time."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security.gentoo.org/glsa/201703-03"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "All PuTTY users should upgrade to the latest version:
          # emerge --sync
          # emerge --ask --oneshot --verbose '>=net-misc/putty-0.68'"
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
      script_set_cvss_temporal_vector("CVSS2#E:POC/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:P/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:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:putty");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2017/03/19");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/03/20");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"Gentoo Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/Gentoo/release", "Host/Gentoo/qpkg-list");
    
      exit(0);
    }
    
    
    include("audit.inc");
    include("global_settings.inc");
    include("qpkg.inc");
    
    if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
    if (!get_kb_item("Host/Gentoo/release")) audit(AUDIT_OS_NOT, "Gentoo");
    if (!get_kb_item("Host/Gentoo/qpkg-list")) audit(AUDIT_PACKAGE_LIST_MISSING);
    
    
    flag = 0;
    
    if (qpkg_check(package:"net-misc/putty", unaffected:make_list("ge 0.68"), vulnerable:make_list("lt 0.68"))) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_hole(port:0, extra:qpkg_report_get());
      else security_hole(0);
      exit(0);
    }
    else
    {
      tested = qpkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "PuTTY");
    }
    

Packetstorm

data sourcehttps://packetstormsecurity.com/files/download/142870/puttysshagent-overflow.txt
idPACKETSTORM:142870
last seen2017-06-09
published2017-06-08
reporterTim Kosse
sourcehttps://packetstormsecurity.com/files/142870/PuTTY-ssh_agent_channel_data-Integer-Overflow.html
titlePuTTY ssh_agent_channel_data Integer Overflow