Vulnerabilities > CVE-2020-11047 - Out-of-bounds Read vulnerability in multiple products

047910
CVSS 5.9 - MEDIUM
Attack vector
NETWORK
Attack complexity
HIGH
Privileges required
HIGH
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
HIGH
network
high complexity
freerdp
canonical
debian
CWE-125
nessus

Summary

In FreeRDP after 1.1 and before 2.0.0, there is an out-of-bounds read in autodetect_recv_bandwidth_measure_results. A malicious server can extract up to 8 bytes of client memory with a manipulated message by providing a short input and reading the measurement result data. This has been patched in 2.0.0.

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Overread Buffers
    An adversary attacks a target by providing input that causes an application to read beyond the boundary of a defined buffer. This typically occurs when a value influencing where to start or stop reading is set to reflect positions outside of the valid memory location of the buffer. This type of attack may result in exposure of sensitive information, a system crash, or arbitrary code execution.

Nessus

NASL familyUbuntu Local Security Checks
NASL idUBUNTU_USN-4379-1.NASL
descriptionIt was discovered that FreeRDP incorrectly handled certain memory operations. A remote attacker could use this issue to cause FreeRDP to crash, resulting in a denial of service, or possibly exeucte arbitrary code. Note that Tenable Network Security has extracted the preceding description block directly from the Ubuntu security advisory. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
last seen2020-06-06
modified2020-06-02
plugin id137045
published2020-06-02
reporterUbuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/137045
titleUbuntu 18.04 LTS / 19.10 / 20.04 : freerdp2 vulnerabilities (USN-4379-1)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Ubuntu Security Notice USN-4379-1. The text 
# itself is copyright (C) Canonical, Inc. See 
# <http://www.ubuntu.com/usn/>. Ubuntu(R) is a registered 
# trademark of Canonical, Inc.
#

include("compat.inc");

if (description)
{
  script_id(137045);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/05");

  script_cve_id("CVE-2018-1000852", "CVE-2019-17177", "CVE-2020-11042", "CVE-2020-11044", "CVE-2020-11045", "CVE-2020-11046", "CVE-2020-11047", "CVE-2020-11048", "CVE-2020-11049", "CVE-2020-11058", "CVE-2020-11521", "CVE-2020-11522", "CVE-2020-11523", "CVE-2020-11524", "CVE-2020-11525", "CVE-2020-11526", "CVE-2020-13396", "CVE-2020-13397", "CVE-2020-13398");
  script_xref(name:"USN", value:"4379-1");

  script_name(english:"Ubuntu 18.04 LTS / 19.10 / 20.04 : freerdp2 vulnerabilities (USN-4379-1)");
  script_summary(english:"Checks dpkg output for updated packages.");

  script_set_attribute(
    attribute:"synopsis",
    value:
"The remote Ubuntu host is missing one or more security-related
patches."
  );
  script_set_attribute(
    attribute:"description",
    value:
"It was discovered that FreeRDP incorrectly handled certain memory
operations. A remote attacker could use this issue to cause FreeRDP to
crash, resulting in a denial of service, or possibly exeucte arbitrary
code.

Note that Tenable Network Security has extracted the preceding
description block directly from the Ubuntu security advisory. 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://usn.ubuntu.com/4379-1/"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Update the affected libfreerdp-client2-2, libfreerdp-server2-2 and /
or libfreerdp2-2 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: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:canonical:ubuntu_linux:libfreerdp-client2-2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp-server2-2");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:canonical:ubuntu_linux:libfreerdp2-2");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:18.04:-:lts");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:19.10");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:canonical:ubuntu_linux:20.04");

  script_set_attribute(attribute:"vuln_publication_date", value:"2018/12/20");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/06/01");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/06/02");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"Ubuntu Security Notice (C) 2020 Canonical, Inc. / NASL script (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"Ubuntu Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/cpu", "Host/Ubuntu", "Host/Ubuntu/release", "Host/Debian/dpkg-l");

  exit(0);
}


include("audit.inc");
include("ubuntu.inc");
include("misc_func.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
release = get_kb_item("Host/Ubuntu/release");
if ( isnull(release) ) audit(AUDIT_OS_NOT, "Ubuntu");
release = chomp(release);
if (! preg(pattern:"^(18\.04|19\.10|20\.04)$", string:release)) audit(AUDIT_OS_NOT, "Ubuntu 18.04 / 19.10 / 20.04", "Ubuntu " + release);
if ( ! get_kb_item("Host/Debian/dpkg-l") ) 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, "Ubuntu", cpu);

flag = 0;

if (ubuntu_check(osver:"18.04", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"18.04", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.18.04.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"19.10", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.19.10.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp-client2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp-server2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) flag++;
if (ubuntu_check(osver:"20.04", pkgname:"libfreerdp2-2", pkgver:"2.1.1+dfsg1-0ubuntu0.20.04.1")) flag++;

if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_HOLE,
    extra      : ubuntu_report_get()
  );
  exit(0);
}
else
{
  tested = ubuntu_pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "libfreerdp-client2-2 / libfreerdp-server2-2 / libfreerdp2-2");
}