Vulnerabilities > CVE-2010-4176 - Incorrect Default Permissions vulnerability in multiple products

047910
CVSS 4.0 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
SINGLE
Confidentiality impact
PARTIAL
Integrity impact
NONE
Availability impact
NONE
network
low complexity
udev-project
dracut-project
CWE-276
nessus
NVD
Published: 2010-12-07
Updated: 2022-06-03

Summary

plymouth-pretrigger.sh in dracut and udev, when running on Fedora 13 and 14, sets weak permissions for the /dev/systty device file, which allows remote authenticated users to read terminal data from tty0 for local users.

Vulnerable Configurations

Part Description Count
Application
Udev_Project
1
Application
Dracut_Project
1
OS
Fedoraproject
2

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Accessing Functionality Not Properly Constrained by ACLs
    In applications, particularly web applications, access to functionality is mitigated by the authorization framework, whose job it is to map ACLs to elements of the application's functionality; particularly URL's for web apps. In the case that the administrator failed to specify an ACL for a particular element, an attacker may be able to access it with impunity. An attacker with the ability to access functionality not properly constrained by ACLs can obtain sensitive information and possibly compromise the entire application. Such an attacker can access resources that must be available only to users at a higher privilege level, can access management sections of the application or can run queries for data that he is otherwise not supposed to.
  • Directory Indexing
    An adversary crafts a request to a target that results in the target listing/indexing the content of a directory as output. One common method of triggering directory contents as output is to construct a request containing a path that terminates in a directory name rather than a file name since many applications are configured to provide a list of the directory's contents when such a request is received. An adversary can use this to explore the directory tree on a target as well as learn the names of files. This can often end up revealing test files, backup files, temporary files, hidden files, configuration files, user accounts, script contents, as well as naming conventions, all of which can be used by an attacker to mount additional attacks.
  • Footprinting
    An attacker engages in probing and exploration activity to identify constituents and properties of the target. Footprinting is a general term to describe a variety of information gathering techniques, often used by attackers in preparation for some attack. It consists of using tools to learn as much as possible about the composition, configuration, and security mechanisms of the targeted application, system or network. Information that might be collected during a footprinting effort could include open ports, applications and their versions, network topology, and similar information. While footprinting is not intended to be damaging (although certain activities, such as network scans, can sometimes cause disruptions to vulnerable applications inadvertently) it may often pave the way for more damaging attacks.
  • Embedding Scripts within Scripts
    An attack of this type exploits a programs' vulnerabilities that are brought on by allowing remote hosts to execute scripts. The attacker leverages this capability to execute scripts to execute his/her own script by embedding it within other scripts that the target software is likely to execute. The attacker must have the ability to inject script into script that is likely to be executed. If this is done, then the attacker can potentially launch a variety of probes and attacks against the web server's local environment, in many cases the so-called DMZ, back end resources the web server can communicate with, and other hosts. With the proliferation of intermediaries, such as Web App Firewalls, network devices, and even printers having JVMs and Web servers, there are many locales where an attacker can inject malicious scripts. Since this attack pattern defines scripts within scripts, there are likely privileges to execute said attack on the host. Of course, these attacks are not solely limited to the server side, client side scripts like Ajax and client side JavaScript can contain malicious scripts as well. In general all that is required is for there to be sufficient privileges to execute a script, but not protected against writing.
  • Web Logs Tampering
    Web Logs Tampering attacks involve an attacker injecting, deleting or otherwise tampering with the contents of web logs typically for the purposes of masking other malicious behavior. Additionally, writing malicious data to log files may target jobs, filters, reports, and other agents that process the logs in an asynchronous attack pattern. This pattern of attack is similar to "Log Injection-Tampering-Forging" except that in this case, the attack is targeting the logs of the web server and not the application.

Nessus

  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2010-17930.NASL
    descriptionIt was discovered that /dev/systty device file created by dracut-generated initramfs scripts used an insecure file permissions. This could possibly allow local user to snoop on other user
    last seen2020-06-01
    modified2020-06-02
    plugin id50814
    published2010-11-28
    reporterThis script is Copyright (C) 2010-2019 Tenable Network Security, Inc.
    sourcehttps://www.tenable.com/plugins/nessus/50814
    titleFedora 14 : dracut-006-5.fc14 / udev-161-7.fc14 (2010-17930)
    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 2010-17930.
#

include("compat.inc");

if (description)
{
  script_id(50814);
  script_version("1.10");
  script_cvs_date("Date: 2019/08/02 13:32:32");

  script_cve_id("CVE-2010-4176");
  script_xref(name:"FEDORA", value:"2010-17930");

  script_name(english:"Fedora 14 : dracut-006-5.fc14 / udev-161-7.fc14 (2010-17930)");
  script_summary(english:"Checks rpm output for the updated packages.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Fedora host is missing one or more security updates."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that /dev/systty device file created by
dracut-generated initramfs scripts used an insecure file permissions.
This could possibly allow local user to snoop on other user's
terminal.

Updated dracut no longer creates this file as device file, rather
creates it a symbolic link to tty0 device file. However, for this
change to take effect, user needs to re-generate initramfs (any
initramfs for all kernels that are going to be booted in the future)
using updated dracut version and reboot the system.

This update also provides updated udev packages that replace systty
device file with a symlink on udev package upgrade and each udev
start. This provides a work-around fix for users that fail to
regenerate their initramfs and reboot as described above.

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora 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://bugzilla.redhat.com/show_bug.cgi?id=654489"
  );
  # https://lists.fedoraproject.org/pipermail/package-announce/2010-November/051417.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?8e0c261a"
  );
  # https://lists.fedoraproject.org/pipermail/package-announce/2010-November/051418.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?15a3afa2"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected dracut and / or udev packages."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:dracut");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:udev");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:14");

  script_set_attribute(attribute:"patch_publication_date", value:"2010/11/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2010/11/28");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2010-2019 Tenable Network Security, Inc.");
  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 = eregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! ereg(pattern:"^14([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 14.x", "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:"FC14", reference:"dracut-006-5.fc14")) flag++;
if (rpm_check(release:"FC14", reference:"udev-161-7.fc14")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "dracut / udev");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2010-17912.NASL
    descriptionIt was discovered that /dev/systty device file created by dracut-generated initramfs scripts used an insecure file permissions. This could possibly allow local user to snoop on other user
    last seen2020-06-01
    modified2020-06-02
    plugin id50972
    published2010-12-03
    reporterThis script is Copyright (C) 2010-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/50972
    titleFedora 13 : udev-153-5.fc13 (2010-17912)
    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 2010-17912.
#

include("compat.inc");

if (description)
{
  script_id(50972);
  script_version("1.12");
  script_cvs_date("Date: 2019/08/02 13:32:32");

  script_cve_id("CVE-2010-4176");
  script_bugtraq_id(45046);
  script_xref(name:"FEDORA", value:"2010-17912");

  script_name(english:"Fedora 13 : udev-153-5.fc13 (2010-17912)");
  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:
"It was discovered that /dev/systty device file created by
dracut-generated initramfs scripts used an insecure file permissions.
This could possibly allow local user to snoop on other user's
terminal.

Updated dracut no longer creates this file as device file, rather
creates it a symbolic link to tty0 device file. However, for this
change to take effect, user needs to re-generate initramfs (any
initramfs for all kernels that are going to be booted in the future)
using updated dracut version and reboot the system.

On Fedora 13, dracut update addressing this flaw was previously
released as bug fix update. This update only provides updated udev
packages that replace systty device file with a symlink on udev
package upgrade and each udev start. This provides a work-around fix
for users that fail to regenerate their initramfs and reboot as
described above.

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora 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://bugzilla.redhat.com/show_bug.cgi?id=654489"
  );
  # https://lists.fedoraproject.org/pipermail/package-announce/2010-December/051755.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?ba1ad7e7"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected udev package.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:P/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");
  script_set_attribute(attribute:"exploit_available", value:"false");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:udev");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:13");

  script_set_attribute(attribute:"patch_publication_date", value:"2010/11/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2010/12/03");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2010-2019 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 = eregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! ereg(pattern:"^13([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 13.x", "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:"FC13", reference:"udev-153-5.fc13")) flag++;


if (flag)
{
  if (report_verbosity > 0) security_warning(port:0, extra:rpm_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "udev");
}

References