Vulnerabilities > CVE-2019-15785 - Improper Restriction of Operations within the Bounds of a Memory Buffer vulnerability in Fontforge

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
fontforge
CWE-119
critical
nessus
NVD
Published: 2019-08-29
Updated: 2024-11-21

Summary

FontForge 20190813 through 20190820 has a buffer overflow in PrefsUI_LoadPrefs in prefs.c.

Vulnerable Configurations

Part Description Count
Application
Fontforge
27

Common Weakness Enumeration (CWE)

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 familyGentoo Local Security Checks
NASL idGENTOO_GLSA-202004-14.NASL
descriptionThe remote host is affected by the vulnerability described in GLSA-202004-14 (FontForge: Multiple vulnerabilities) Multiple vulnerabilities have been discovered in FontForge. Please review the CVE identifiers referenced below for details. Impact : A remote attacker could entice a user to open a specially crafted font using FontForge, possibly resulting in execution of arbitrary code with the privileges of the process or a Denial of Service condition. Workaround : There is no known workaround at this time.
last seen2020-05-08
modified2020-05-01
plugin id136213
published2020-05-01
reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/136213
titleGLSA-202004-14 : FontForge: 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 202004-14.
#
# The advisory text is Copyright (C) 2001-2020 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(136213);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/05/07");

  script_cve_id("CVE-2019-15785", "CVE-2020-5395", "CVE-2020-5496");
  script_xref(name:"GLSA", value:"202004-14");

  script_name(english:"GLSA-202004-14 : FontForge: 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-202004-14
(FontForge: Multiple vulnerabilities)

    Multiple vulnerabilities have been discovered in FontForge. Please
      review the CVE identifiers referenced below for details.
  
Impact :

    A remote attacker could entice a user to open a specially crafted font
      using FontForge, possibly resulting in execution of arbitrary code with
      the privileges of the process or 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/202004-14"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All FontForge users should upgrade to the latest version:
      # emerge --sync
      # emerge --ask --oneshot --verbose '>=media-gfx/fontforge-20200314'"
  );
  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:U/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: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:gentoo:linux:fontforge");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/08/29");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/04/30");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/05/01");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2020 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:"media-gfx/fontforge", unaffected:make_list("ge 20200314"), vulnerable:make_list("lt 20200314"))) 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, "FontForge");
}

References