Vulnerabilities > CVE-2019-3467 - Incorrect Permission Assignment for Critical Resource vulnerability in multiple products

047910
CVSS 7.8 - HIGH
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
HIGH
Availability impact
HIGH
local
low complexity
debian
skolelinux
canonical
CWE-732
nessus
NVD
Published: 2019-12-23
Updated: 2024-11-21

Summary

Debian-edu-config all versions < 2.11.10, a set of configuration files used for Debian Edu, and debian-lan-config < 0.26, configured too permissive ACLs for the Kerberos admin server, which allowed password changes for other Kerberos user principals.

Vulnerable Configurations

Part Description Count
Application
Debian
4
Application
Skolelinux
4
OS
Debian
3
OS
Canonical
1

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.
  • Privilege Abuse
    An adversary is able to exploit features of the target that should be reserved for privileged users or administrators but are exposed to use by lower or non-privileged accounts. Access to sensitive information and functionality must be controlled to ensure that only authorized users are able to access these resources. If access control mechanisms are absent or misconfigured, a user may be able to access resources that are intended only for higher level users. An adversary may be able to exploit this to utilize a less trusted account to gain information and perform activities reserved for more trusted accounts. This attack differs from privilege escalation and other privilege stealing attacks in that the adversary never actually escalates their privileges but instead is able to use a lesser degree of privilege to access resources that should be (but are not) reserved for higher privilege accounts. Likewise, the adversary does not exploit trust or subvert systems - all control functionality is working as configured but the configuration does not adequately protect sensitive resources at an appropriate level.
  • 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.
  • 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.
  • Exploiting Incorrectly Configured Access Control Security Levels
    An attacker exploits a weakness in the configuration of access controls and is able to bypass the intended protection that these measures guard against and thereby obtain unauthorized access to the system or network. Sensitive functionality should always be protected with access controls. However configuring all but the most trivial access control systems can be very complicated and there are many opportunities for mistakes. If an attacker can learn of incorrectly configured access security settings, they may be able to exploit this in an attack. Most commonly, attackers would take advantage of controls that provided too little protection for sensitive activities in order to perform actions that should be denied to them. In some circumstances, an attacker may be able to take advantage of overly restrictive access control policies, initiating denial of services (if an application locks because it unexpectedly failed to be granted access) or causing other legitimate actions to fail due to security. The latter class of attacks, however, is usually less severe and easier to detect than attacks based on inadequate security restrictions. This attack pattern differs from CAPEC 1, "Accessing Functionality Not Properly Constrained by ACLs" in that the latter describes attacks where sensitive functionality lacks access controls, where, in this pattern, the access control is present, but incorrectly configured.

Nessus

  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-2063.NASL
    descriptionIn debian-lan-config < 0.26, configured too permissive ACLs for the Kerberos admin server allowed password changes for other Kerberos user principals. For Debian 8
    last seen2020-06-01
    modified2020-06-02
    plugin id132941
    published2020-01-16
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132941
    titleDebian DLA-2063-1 : debian-lan-config security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-2063-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(132941);
  script_version("1.2");
  script_cvs_date("Date: 2020/01/21");

  script_cve_id("CVE-2019-3467");

  script_name(english:"Debian DLA-2063-1 : debian-lan-config security update");
  script_summary(english:"Checks dpkg output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"In debian-lan-config < 0.26, configured too permissive ACLs for the
Kerberos admin server allowed password changes for other Kerberos user
principals.

For Debian 8 'Jessie', this problem has been fixed in version
0.19+deb8u2.

We recommend that you upgrade your debian-lan-config 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/2020/01/msg00012.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/debian-lan-config"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Upgrade the affected debian-lan-config package."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/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:debian-lan-config");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/12/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/01/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/01/16");
  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:"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:"debian-lan-config", reference:"0.19+deb8u2")) 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");
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DLA-2041.NASL
    descriptionIt was discovered that debian-edu-config, the package containing the configuration files and scripts for Debian Edu (Skolelinux), contained an insecure configuration for kadmin, the Kerberos administration server. The insecure configuration allowed every user to change other users
    last seen2020-06-01
    modified2020-06-02
    plugin id132267
    published2019-12-19
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132267
    titleDebian DLA-2041-1 : debian-edu-config security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from Debian Security Advisory DLA-2041-1. The text
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(132267);
  script_version("1.4");
  script_cvs_date("Date: 2020/01/07");

  script_cve_id("CVE-2019-3467");

  script_name(english:"Debian DLA-2041-1 : debian-edu-config security update");
  script_summary(english:"Checks dpkg output for the updated package.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that debian-edu-config, the package containing the
configuration files and scripts for Debian Edu (Skolelinux), contained
an insecure configuration for kadmin, the Kerberos administration
server. The insecure configuration allowed every user to change other
users' passwords, thus impersonating them and possibly gaining their
privileges.

The bug was not exposed in the officially documented user management
frontends of Debian Edu, but could be abused by local network users
knowing how to use the Kerberos backend.

For Debian 8 'Jessie', this problem has been fixed in version
1.818+deb8u3.

We recommend that you upgrade your debian-edu-config 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/2019/12/msg00023.html"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/jessie/debian-edu-config"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Upgrade the affected debian-edu-config package."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/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:"cvss_score_source", value:"CVE-2019-3467");
  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:debian-edu-config");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:8.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/12/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/12/18");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/19");
  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:"debian-edu-config", reference:"1.818+deb8u3")) 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");
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-4595.NASL
    descriptionIt was discovered that debian-lan-config, a FAI config space for the Debian-LAN system, configured too permissive ACLs for the Kerberos admin server, which allowed password changes for other user principals. This update provides a fixed configuration for new deployments, for existing setups, the NEWS file shipped in this update provides advice to fix the configuration.
    last seen2020-06-01
    modified2020-06-02
    plugin id132426
    published2019-12-30
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132426
    titleDebian DSA-4595-1 : debian-lan-config - security update
    code
    #
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from Debian Security Advisory DSA-4595. The text 
# itself is copyright (C) Software in the Public Interest, Inc.
#

include("compat.inc");

if (description)
{
  script_id(132426);
  script_version("1.4");
  script_cvs_date("Date: 2020/01/07");

  script_cve_id("CVE-2019-3467");
  script_xref(name:"DSA", value:"4595");

  script_name(english:"Debian DSA-4595-1 : debian-lan-config - security update");
  script_summary(english:"Checks dpkg output for the updated package");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote Debian host is missing a security-related update."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"It was discovered that debian-lan-config, a FAI config space for the
Debian-LAN system, configured too permissive ACLs for the Kerberos
admin server, which allowed password changes for other user
principals.

This update provides a fixed configuration for new deployments, for
existing setups, the NEWS file shipped in this update provides advice
to fix the configuration."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=947459"
  );
  # https://security-tracker.debian.org/tracker/source-package/debian-lan-config
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?bbd0d795"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/stretch/debian-lan-config"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://packages.debian.org/source/buster/debian-lan-config"
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://www.debian.org/security/2019/dsa-4595"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Upgrade the debian-lan-config packages.

For the oldstable distribution (stretch), this problem has been fixed
in version 0.23+deb9u1.

For the stable distribution (buster), this problem has been fixed in
version 0.25+deb10u1."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:C/I:C/A:C");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/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:"cvss_score_source", value:"CVE-2019-3467");
  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:debian-lan-config");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:10.0");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:debian:debian_linux:9.0");

  script_set_attribute(attribute:"vuln_publication_date", value:"2019/12/23");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/12/27");
  script_set_attribute(attribute:"plugin_publication_date", value:"2019/12/30");
  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:"10.0", prefix:"debian-lan-config", reference:"0.25+deb10u1")) flag++;
if (deb_check(release:"9.0", prefix:"debian-lan-config", reference:"0.23+deb9u1")) 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");
  • NASL familyDebian Local Security Checks
    NASL idDEBIAN_DSA-4589.NASL
    descriptionIt was discovered that debian-edu-config, a set of configuration files used for the Debian Edu blend, configured too permissive ACLs for the Kerberos admin server, which allowed password changes for other user principals.
    last seen2020-06-01
    modified2020-06-02
    plugin id132269
    published2019-12-19
    reporterThis script is Copyright (C) 2019-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/132269
    titleDebian DSA-4589-1 : debian-edu-config - security update

References