Vulnerabilities > CVE-2017-16671 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Digium Asterisk and Certified Asterisk

047910
CVSS 6.5 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
network
low complexity
digium
CWE-119
nessus

Summary

A Buffer Overflow issue was discovered in Asterisk Open Source 13 before 13.18.1, 14 before 14.7.1, and 15 before 15.1.1 and Certified Asterisk 13.13 before 13.13-cert7. No size checking is done when setting the user field for Party B on a CDR. Thus, it is possible for someone to use an arbitrarily large string and write past the end of the user field storage buffer. NOTE: this is different from CVE-2017-7617, which was only about the Party A buffer.

Vulnerable Configurations

Part Description Count
Application
Digium
137

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.

Nessus

  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-4076.NASL
    descriptionMultiple vulnerabilities have been discovered in Asterisk, an open source PBX and telephony toolkit, which may result in denial of service, information disclosure and potentially the execution of arbitrary code.
    last seen2020-06-01
    modified2020-06-02
    plugin id105498
    published2018-01-02
    reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/105498
    titleDebian DSA-4076-1 : asterisk - security update
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were  
    # extracted from Debian Security Advisory DSA-4076. The text 
    # itself is copyright (C) Software in the Public Interest, Inc.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(105498);
      script_version("3.5");
      script_cvs_date("Date: 2019/04/05 23:25:05");
    
      script_cve_id("CVE-2017-16671", "CVE-2017-16672", "CVE-2017-17090", "CVE-2017-17664");
      script_xref(name:"DSA", value:"4076");
    
      script_name(english:"Debian DSA-4076-1 : asterisk - security update");
      script_summary(english:"Checks dpkg output for the updated package");
    
      script_set_attribute(
        attribute:"synopsis", 
        value:"The remote Debian host is missing a security-related update."
      );
      script_set_attribute(
        attribute:"description", 
        value:
    "Multiple vulnerabilities have been discovered in Asterisk, an open
    source PBX and telephony toolkit, which may result in denial of
    service, information disclosure and potentially the execution of
    arbitrary code."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security-tracker.debian.org/tracker/source-package/asterisk"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://packages.debian.org/source/jessie/asterisk"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://packages.debian.org/source/stretch/asterisk"
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://www.debian.org/security/2017/dsa-4076"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "Upgrade the asterisk packages.
    
    For the oldstable distribution (jessie), these problems have been
    fixed in version 1:11.13.1~dfsg-2+deb8u5.
    
    For the stable distribution (stretch), these problems have been fixed
    in version 1:13.14.1~dfsg-2+deb9u3."
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/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:L/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:debian:debian_linux:asterisk");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:9.0");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2017/12/30");
      script_set_attribute(attribute:"plugin_publication_date", value:"2018/01/02");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
      script_family(english:"Debian Local Security Checks");
    
      script_dependencies("ssh_get_info.nasl");
      script_require_keys("Host/local_checks_enabled", "Host/Debian/release", "Host/Debian/dpkg-l");
    
      exit(0);
    }
    
    
    include("audit.inc");
    include("debian_package.inc");
    
    
    if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
    if (!get_kb_item("Host/Debian/release")) audit(AUDIT_OS_NOT, "Debian");
    if (!get_kb_item("Host/Debian/dpkg-l")) audit(AUDIT_PACKAGE_LIST_MISSING);
    
    
    flag = 0;
    if (deb_check(release:"8.0", prefix:"asterisk", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-config", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-dahdi", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-dbg", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-dev", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-doc", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-mobile", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-modules", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-mp3", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-mysql", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-ooh323", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-voicemail", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-voicemail-imapstorage", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-voicemail-odbcstorage", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"8.0", prefix:"asterisk-vpb", reference:"1:11.13.1~dfsg-2+deb8u5")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-config", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-dahdi", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-dev", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-doc", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-mobile", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-modules", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-mp3", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-mysql", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-ooh323", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-voicemail", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-voicemail-imapstorage", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-voicemail-odbcstorage", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    if (deb_check(release:"9.0", prefix:"asterisk-vpb", reference:"1:13.14.1~dfsg-2+deb9u3")) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_warning(port:0, extra:deb_report_get());
      else security_warning(0);
      exit(0);
    }
    else audit(AUDIT_HOST_NOT, "affected");
    
  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201811-11.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201811-11 (Asterisk: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in Asterisk. Please review the referenced CVE identifiers for details. Impact : A remote attacker could cause a Denial of Service condition or conduct information gathering. Workaround : There is no known workaround at this time.
    last seen2020-06-01
    modified2020-06-02
    plugin id119131
    published2018-11-26
    reporterThis script is Copyright (C) 2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/119131
    titleGLSA-201811-11 : Asterisk: Multiple vulnerabilities
    code
    #
    # (C) Tenable Network Security, Inc.
    #
    # The descriptive text and package checks in this plugin were
    # extracted from Gentoo Linux Security Advisory GLSA 201811-11.
    #
    # 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(119131);
      script_version("1.1");
      script_cvs_date("Date: 2018/11/26 11:02:12");
    
      script_cve_id("CVE-2017-16671", "CVE-2017-16672", "CVE-2017-17850", "CVE-2018-12227", "CVE-2018-17281");
      script_xref(name:"GLSA", value:"201811-11");
    
      script_name(english:"GLSA-201811-11 : Asterisk: Multiple vulnerabilities");
      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-201811-11
    (Asterisk: Multiple vulnerabilities)
    
        Multiple vulnerabilities have been discovered in Asterisk. Please review
          the referenced CVE identifiers for details.
      
    Impact :
    
        A remote attacker could cause a Denial of Service condition or conduct
          information gathering.
      
    Workaround :
    
        There is no known workaround at this time."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security.gentoo.org/glsa/201811-11"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "All Asterisk users should upgrade to the latest version:
          # emerge --sync
          # emerge --ask --oneshot --verbose '>=net-misc/asterisk-13.23.1'"
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:P/A:P");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:L/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:gentoo:linux:asterisk");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2018/11/24");
      script_set_attribute(attribute:"plugin_publication_date", value:"2018/11/26");
      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:"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/asterisk", unaffected:make_list("ge 13.23.1"), vulnerable:make_list("lt 13.23.1"))) flag++;
    
    if (flag)
    {
      if (report_verbosity > 0) security_warning(port:0, extra:qpkg_report_get());
      else security_warning(0);
      exit(0);
    }
    else
    {
      tested = qpkg_tests_get();
      if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
      else audit(AUDIT_PACKAGE_NOT_INSTALLED, "Asterisk");
    }
    
  • NASL familyFreeBSD Local Security Checks
    NASL idFREEBSD_PKG_AB04CB0BC53311E78DA5001999F8D30B.NASL
    descriptionThe Asterisk project reports : No size checking is done when setting the user field for Party B on a CDR. Thus, it is possible for someone to use an arbitrarily large string and write past the end of the user field storage buffer. The earlier AST-2017-001 advisory for the CDR user field overflow was for the Party A buffer.
    last seen2020-06-01
    modified2020-06-02
    plugin id104490
    published2017-11-10
    reporterThis script is Copyright (C) 2017-2018 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/104490
    titleFreeBSD : asterisk -- Buffer overflow in CDR's set user (ab04cb0b-c533-11e7-8da5-001999f8d30b)
  • NASL familyMisc.
    NASL idASTERISK_AST_2017_009-011.NASL
    descriptionAccording to its SIP banner, the version of Asterisk running on the remote host is 13.x prior to 13.18.1, 14.x prior to 14.7.1, 15.x prior to 15.1.1, or 13.13 prior to 13.13-cert7. It is therefore, affected by multiple vulnerabilities as described in AST-2017-009, AST-2017-010, and AST-2017-011. Also note that Nessus has not tested for these issues but has instead relied only on the application
    last seen2020-06-01
    modified2020-06-02
    plugin id104658
    published2017-11-17
    reporterThis script is Copyright (C) 2017-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/104658
    titleAsterisk 13.x < 13.18.1 / 14.x < 14.7.1 / 15.x < 15.1.1 / 13.13 < 13.13-cert7 Multiple Vulnerabilities (AST-2017-009 - AST-2017-011)