Vulnerabilities > CVE-2016-7970 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in multiple products

047910
CVSS 7.5 - HIGH
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
NONE
Availability impact
HIGH
network
low complexity
fedoraproject
libass-project
CWE-119
nessus

Summary

Buffer overflow in the calc_coeff function in libass/ass_blur.c in libass before 0.13.4 allows remote attackers to cause a denial of service via unspecified vectors.

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 familyFedora Local Security Checks
    NASL idFEDORA_2016-95407A836F.NASL
    descriptionFixes CVE-2016-7969, CVE-2016-7970 and CVE-2016-7972 ---- Update to 0.13.3. Contains various bugfixes. 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
    modified2016-11-03
    plugin id94487
    published2016-11-03
    reporterThis script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/94487
    titleFedora 23 : libass (2016-95407a836f)
    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-2016-95407a836f.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(94487);
      script_version("2.4");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");
    
      script_cve_id("CVE-2016-7969", "CVE-2016-7970", "CVE-2016-7972");
      script_xref(name:"FEDORA", value:"2016-95407a836f");
    
      script_name(english:"Fedora 23 : libass (2016-95407a836f)");
      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:
    "Fixes CVE-2016-7969, CVE-2016-7970 and CVE-2016-7972
    
    ----
    
    Update to 0.13.3.
    
    Contains various bugfixes.
    
    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-2016-95407a836f"
      );
      script_set_attribute(
        attribute:"solution", 
        value:"Update the affected libass package."
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:libass");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:23");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2017/03/03");
      script_set_attribute(attribute:"patch_publication_date", value:"2016/11/01");
      script_set_attribute(attribute:"plugin_publication_date", value:"2016/11/03");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2016-2020 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:"^23([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 23", "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:"FC23", reference:"libass-0.13.4-1.fc23")) 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, "libass");
    }
    
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2016-D2A05A0644.NASL
    descriptionFixes CVE-2016-7969, CVE-2016-7970 and CVE-2016-7972 ---- Update to 0.13.3. Contains various bugfixes. 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
    modified2016-11-15
    plugin id94865
    published2016-11-15
    reporterThis script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/94865
    titleFedora 25 : libass (2016-d2a05a0644)
    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-2016-d2a05a0644.
    #
    
    include("compat.inc");
    
    if (description)
    {
      script_id(94865);
      script_version("2.4");
      script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");
    
      script_cve_id("CVE-2016-7969", "CVE-2016-7970", "CVE-2016-7972");
      script_xref(name:"FEDORA", value:"2016-d2a05a0644");
    
      script_name(english:"Fedora 25 : libass (2016-d2a05a0644)");
      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:
    "Fixes CVE-2016-7969, CVE-2016-7970 and CVE-2016-7972
    
    ----
    
    Update to 0.13.3.
    
    Contains various bugfixes.
    
    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-2016-d2a05a0644"
      );
      script_set_attribute(
        attribute:"solution", 
        value:"Update the affected libass package."
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:libass");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:25");
    
      script_set_attribute(attribute:"vuln_publication_date", value:"2017/03/03");
      script_set_attribute(attribute:"patch_publication_date", value:"2016/10/28");
      script_set_attribute(attribute:"plugin_publication_date", value:"2016/11/15");
      script_set_attribute(attribute:"generated_plugin", value:"current");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2016-2020 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:"libass-0.13.4-1.fc25")) 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, "libass");
    }
    
  • NASL familyGentoo Local Security Checks
    NASL idGENTOO_GLSA-201702-25.NASL
    descriptionThe remote host is affected by the vulnerability described in GLSA-201702-25 (libass: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in libass. Please review the CVE identifiers referenced below for details. Impact : A remote attacker could cause a Denial of Service condition or other unknown impacts via unknown attack vectors. Workaround : There is no known workaround at this time.
    last seen2020-06-01
    modified2020-06-02
    plugin id97268
    published2017-02-21
    reporterThis script is Copyright (C) 2017 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/97268
    titleGLSA-201702-25 : libass: 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 201702-25.
    #
    # The advisory text is Copyright (C) 2001-2017 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(97268);
      script_version("$Revision: 3.2 $");
      script_cvs_date("$Date: 2017/03/06 14:38:26 $");
    
      script_cve_id("CVE-2016-7969", "CVE-2016-7970", "CVE-2016-7971", "CVE-2016-7972");
      script_xref(name:"GLSA", value:"201702-25");
    
      script_name(english:"GLSA-201702-25 : libass: 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-201702-25
    (libass: Multiple vulnerabilities)
    
        Multiple vulnerabilities have been discovered in libass. Please review
          the CVE identifiers referenced below for details.
      
    Impact :
    
        A remote attacker could cause a Denial of Service condition or other
          unknown impacts via unknown attack vectors.
      
    Workaround :
    
        There is no known workaround at this time."
      );
      script_set_attribute(
        attribute:"see_also",
        value:"https://security.gentoo.org/glsa/201702-25"
      );
      script_set_attribute(
        attribute:"solution", 
        value:
    "All libass users should upgrade to the latest version:
          # emerge --sync
          # emerge --ask --oneshot --verbose '>=media-libs/libass-0.13.4'"
      );
      script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:N/I:N/A:P");
      script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H");
    
      script_set_attribute(attribute:"plugin_type", value:"local");
      script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:libass");
      script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");
    
      script_set_attribute(attribute:"patch_publication_date", value:"2017/02/20");
      script_set_attribute(attribute:"plugin_publication_date", value:"2017/02/21");
      script_end_attributes();
    
      script_category(ACT_GATHER_INFO);
      script_copyright(english:"This script is Copyright (C) 2017 Tenable Network Security, Inc.");
      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:"media-libs/libass", unaffected:make_list("ge 0.13.4"), vulnerable:make_list("lt 0.13.4"))) 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, "libass");
    }
    
  • NASL familySuSE Local Security Checks
    NASL idSUSE_SU-2016-3107-1.NASL
    descriptionThis update for libass fixes the following issues: CVE-2016-7969, CVE-2016-7970, CVE-2016-7971, CVE-2016-7972: Fixed multiple memory allocation issues found by fuzzing (bsc#1002982). Note that Tenable Network Security has extracted the preceding description block directly from the SUSE 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 id95798
    published2016-12-14
    reporterThis script is Copyright (C) 2016-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/95798
    titleSUSE SLED12 / SLES12 Security Update : libass (SUSE-SU-2016:3107-1)
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2016-282507C3E9.NASL
    descriptionFixes CVE-2016-7969, CVE-2016-7970 and CVE-2016-7972 ---- Update to 0.13.3. Contains various bugfixes. 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
    modified2016-10-25
    plugin id94235
    published2016-10-25
    reporterThis script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/94235
    titleFedora 24 : libass (2016-282507c3e9)