Vulnerabilities > CVE-2007-5940 - Link Following vulnerability in TUG Texlive 2007

047910
CVSS 4.6 - MEDIUM
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
PARTIAL
Integrity impact
PARTIAL
Availability impact
PARTIAL
local
low complexity
tug
CWE-59
nessus

Summary

feynmf.pl in feynmf 1.08, as used in TeXLive 2007, allows local users to overwrite arbitrary files and execute arbitrary code via a symlink attack on the feynmf$$.pl temporary file.

Vulnerable Configurations

Part Description Count
Application
Tug
1

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Symlink Attack
    An attacker positions a symbolic link in such a manner that the targeted user or application accesses the link's endpoint, assuming that it is accessing a file with the link's name. The endpoint file may be either output or input. If the file is output, the result is that the endpoint is modified, instead of a file at the intended location. Modifications to the endpoint file may include appending, overwriting, corrupting, changing permissions, or other modifications. In some variants of this attack the attacker may be able to control the change to a file while in other cases they cannot. The former is especially damaging since the attacker may be able to grant themselves increased privileges or insert false information, but the latter can also be damaging as it can expose sensitive information or corrupt or destroy vital system or application files. Alternatively, the endpoint file may serve as input to the targeted application. This can be used to feed malformed input into the target or to cause the target to process different information, possibly allowing the attacker to control the actions of the target or to cause the target to expose information to the attacker. Moreover, the actions taken on the endpoint file are undertaken with the permissions of the targeted user or application, which may exceed the permissions that the attacker would normally have.
  • Accessing, Modifying or Executing Executable Files
    An attack of this type exploits a system's configuration that allows an attacker to either directly access an executable file, for example through shell access; or in a possible worst case allows an attacker to upload a file and then execute it. Web servers, ftp servers, and message oriented middleware systems which have many integration points are particularly vulnerable, because both the programmers and the administrators must be in synch regarding the interfaces and the correct privileges for each interface.
  • Leverage Executable Code in Non-Executable Files
    An attack of this type exploits a system's trust in configuration and resource files, when the executable loads the resource (such as an image file or configuration file) the attacker has modified the file to either execute malicious code directly or manipulate the target process (e.g. application server) to execute based on the malicious configuration parameters. Since systems are increasingly interrelated mashing up resources from local and remote sources the possibility of this attack occurring is high. The attack can be directed at a client system, such as causing buffer overrun through loading seemingly benign image files, as in Microsoft Security Bulletin MS04-028 where specially crafted JPEG files could cause a buffer overrun once loaded into the browser. Another example targets clients reading pdf files. In this case the attacker simply appends javascript to the end of a legitimate url for a pdf (http://www.gnucitizen.org/blog/danger-danger-danger/) http://path/to/pdf/file.pdf#whatever_name_you_want=javascript:your_code_here The client assumes that they are reading a pdf, but the attacker has modified the resource and loaded executable javascript into the client's browser process. The attack can also target server processes. The attacker edits the resource or configuration file, for example a web.xml file used to configure security permissions for a J2EE app server, adding role name "public" grants all users with the public role the ability to use the administration functionality. The server trusts its configuration file to be correct, but when they are manipulated, the attacker gains full control.
  • Manipulating Input to File System Calls
    An attacker manipulates inputs to the target software which the target software passes to file system calls in the OS. The goal is to gain access to, and perhaps modify, areas of the file system that the target software did not intend to be accessible.

Nessus

NASL familyGentoo Local Security Checks
NASL idGENTOO_GLSA-200711-32.NASL
descriptionThe remote host is affected by the vulnerability described in GLSA-200711-32 (Feynmf: Insecure temporary file creation) Kevin B. McCarty discovered that the feynmf.pl script creates a temporary
last seen2020-06-01
modified2020-06-02
plugin id28321
published2007-11-26
reporterThis script is Copyright (C) 2007-2019 Tenable Network Security, Inc.
sourcehttps://www.tenable.com/plugins/nessus/28321
titleGLSA-200711-32 : Feynmf: Insecure temporary file creation
code
#%NASL_MIN_LEVEL 80502
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Gentoo Linux Security Advisory GLSA 200711-32.
#
# The advisory text is Copyright (C) 2001-2014 Gentoo Foundation, Inc.
# and licensed under the Creative Commons - Attribution / Share Alike 
# license. See http://creativecommons.org/licenses/by-sa/2.5/
#

include("compat.inc");

if (description)
{
  script_id(28321);
  script_version("1.15");
  script_cvs_date("Date: 2019/08/02 13:32:44");

  script_cve_id("CVE-2007-5940");
  script_xref(name:"GLSA", value:"200711-32");

  script_name(english:"GLSA-200711-32 : Feynmf: Insecure temporary file creation");
  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-200711-32
(Feynmf: Insecure temporary file creation)

    Kevin B. McCarty discovered that the feynmf.pl script creates a
    temporary 'properly list' file at the location '$TMPDIR/feynmf$PID.pl',
    where $PID is the process ID.
  
Impact :

    A local attacker could create symbolic links in the directory where the
    temporary files are written, pointing to a valid file somewhere on the
    filesystem that is writable by the user running Feynmf. When Feynmf
    writes the temporary file, the target valid file would then be
    overwritten with the contents of the Feynmf temporary file.
  
Workaround :

    There is no known workaround at this time."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.gentoo.org/security/en/glsa/glsa-200711-32.xml"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"All Feynmf users should upgrade to the latest version:
    # emerge --sync
    # emerge --ask --oneshot --verbose '>=dev-tex/feynmf-1.08-r2'"
  );
  script_set_attribute(attribute:"risk_factor", value:"Medium");
  script_cwe_id(59);

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:gentoo:linux:feynmf");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:gentoo:linux");

  script_set_attribute(attribute:"patch_publication_date", value:"2007/11/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2007/11/26");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2007-2019 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:"dev-tex/feynmf", unaffected:make_list("ge 1.08-r2"), vulnerable:make_list("lt 1.08-r2"))) 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, "Feynmf");
}