Vulnerabilities > CVE-2019-7653 - Uncontrolled Search Path Element 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
rdflib-project
debian
canonical
CWE-427
critical
nessus
NVD
Published: 2019-02-09
Updated: 2024-11-21

Summary

The Debian python-rdflib-tools 4.2.2-1 package for RDFLib 4.2.2 has CLI tools that can load Python modules from the current working directory, allowing code injection, because "python -m" looks in this directory, as demonstrated by rdf2dot. This issue is specific to use of the debian/scripts directory.

Vulnerable Configurations

Part Description Count
Application
Rdflib_Project
1
OS
Debian
2
OS
Canonical
1

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Leveraging/Manipulating Configuration File Search Paths
    This attack loads a malicious resource into a program's standard path used to bootstrap and/or provide contextual information for a program like a path variable or classpath. J2EE applications and other component based applications that are built from multiple binaries can have very long list of dependencies to execute. If one of these libraries and/or references is controllable by the attacker then application controls can be circumvented by the attacker. A standard UNIX path looks similar to this If the attacker modifies the path variable to point to a locale that includes malicious resources then the user unwittingly can execute commands on the attackers' behalf: This is a form of usurping control of the program and the attack can be done on the classpath, database resources, or any other resources built from compound parts. At runtime detection and blocking of this attack is nearly impossible, because the configuration allows execution.
  • DLL Search Order Hijacking
    The attacker exploits the functionality of the Windows DLL loader where the process loading the DLL searches for the DLL to be loaded first in the same directory in which the process binary resides and then in other directories (e.g., System32). Exploitation of this preferential search order can allow an attacker to make the loading process load the attackers' rogue DLL rather than the legitimate DLL. For instance, an attacker with access to the file system may place a malicious ntshrui.dll in the C:\Windows directory. This DLL normally resides in the System32 folder. Process explorer.exe which also resides in C:\Windows, upon trying to load the ntshrui.dll from the System32 folder will actually load the DLL supplied by the attacker simply because of the preferential search order. Since the attacker has placed its malicious ntshrui.dll in the same directory as the loading explorer.exe process, the DLL supplied by the attacker will be found first and thus loaded in lieu of the legitimate DLL. Since explorer.exe is loaded during the boot cycle, the attackers' malware is guaranteed to execute. This attack can be leveraged with many different DLLs and with many different loading processes. No forensic trails are left in the system's registry or file system that an incorrect DLL had been loaded.

Nessus

NASL familyDebian Local Security Checks
NASL idDEBIAN_DLA-1717.NASL
descriptionThe CLI tools in python-rdflib-tools can load python modules found in the current directory. This happens because
last seen2020-06-01
modified2020-06-02
plugin id122929
published2019-03-19
reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/122929
titleDebian DLA-1717-1 : rdflib security update
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-1717-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(122929);
  script_version("1.2");
  script_cvs_date("Date: 2020/02/05");

  script_cve_id("CVE-2019-7653");

  script_name(english:"Debian DLA-1717-1 : rdflib security update");
  script_summary(english:"Checks dpkg output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"The CLI tools in python-rdflib-tools can load python modules found in
the current directory. This happens because 'python -m' appends the
current directory in the python path.

For Debian 8 'Jessie', this problem has been fixed in version
4.1.2-3+deb8u1.

We recommend that you upgrade your rdflib packages.

NOTE: Tenable Network Security has extracted the preceding description
block directly from the DLA 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://lists.debian.org/debian-lts-announce/2019/03/msg00019.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/rdflib"
  );
  script_set_attribute(attribute:"solution", value:"Upgrade the affected 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:debian:debian_linux:python-rdflib");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-rdflib-doc");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python-rdflib-tools");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:debian:debian_linux:python3-rdflib");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/02/09");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/03/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/03/19");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2019-2020 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:"python-rdflib", reference:"4.1.2-3+deb8u1")) flag++;
if (deb_check(release:"8.0", prefix:"python-rdflib-doc", reference:"4.1.2-3+deb8u1")) flag++;
if (deb_check(release:"8.0", prefix:"python-rdflib-tools", reference:"4.1.2-3+deb8u1")) flag++;
if (deb_check(release:"8.0", prefix:"python3-rdflib", reference:"4.1.2-3+deb8u1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:deb_report_get());
  else security_hole(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");

References