Vulnerabilities > CVE-2018-15321 - Improper Privilege Management vulnerability in F5 products

047910
CVSS 4.9 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
HIGH
Confidentiality impact
NONE
Integrity impact
HIGH
Availability impact
NONE
network
low complexity
f5
CWE-269
nessus
NVD
Published: 2018-10-31
Updated: 2019-10-03

Summary

When BIG-IP 14.0.0-14.0.0.2, 13.0.0-13.1.0.5, 12.1.0-12.1.3.5, 11.6.0-11.6.3.2, or 11.2.1-11.5.6, BIG-IQ Centralized Management 5.0.0-5.4.0 or 4.6.0, BIG-IQ Cloud and Orchestration 1.0.0, iWorkflow 2.1.0-2.3.0, or Enterprise Manager 3.1.1 is licensed for Appliance Mode, Admin and Resource administrator roles can by-pass BIG-IP Appliance Mode restrictions to overwrite critical system files. Attackers of high privilege level are able to overwrite critical system files which bypasses security controls in place to limit TMSH commands. This is possible with an administrator or resource administrator roles when granted TMSH. Resource administrator roles must have TMSH access in order to perform this attack.

Vulnerable Configurations

Part Description Count
Application
F5
691

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Restful Privilege Elevation
    Rest uses standard HTTP (Get, Put, Delete) style permissions methods, but these are not necessarily correlated generally with back end programs. Strict interpretation of HTTP get methods means that these HTTP Get services should not be used to delete information on the server, but there is no access control mechanism to back up this logic. This means that unless the services are properly ACL'd and the application's service implementation are following these guidelines then an HTTP request can easily execute a delete or update on the server side. The attacker identifies a HTTP Get URL such as http://victimsite/updateOrder, which calls out to a program to update orders on a database or other resource. The URL is not idempotent so the request can be submitted multiple times by the attacker, additionally, the attacker may be able to exploit the URL published as a Get method that actually performs updates (instead of merely retrieving data). This may result in malicious or inadvertent altering of data on the server.

Nessus

NASL familyF5 Networks Local Security Checks
NASL idF5_BIGIP_SOL01067037.NASL
descriptionWhen BIG-IP is licensed for Appliance mode, Admin and Resource administrator roles can by-pass BIG-IP Appliance mode restrictions to overwrite critical system files. (CVE-2018-15321) Attackers with ahigh-privilege level can overwrite critical system files, which in turnbypasses security controls thatlimit TMOS Shell ( tmsh ) commands.This scenario is possible when the Administrator orResource Administrator roles are granted tmsh access.Resource Administrator roles must have tmsh access to perform this attack. Note : F5 does not consider the capability of Advanced Shell ( bash ) access in this vulnerability, as users granted that level of access can simply perform any command as root. This vulnerability is an issue for Appliance mode, users who are granted tmsh access, and for the Resource Administrator role when operating in standard, non-Appliance mode. Impact When the BIG-IP system is licensed for Appliance mode, Administrator and Resource Administrator roles can by-pass BIG-IP Appliance mode restrictions to overwrite critical system files.
last seen2020-06-01
modified2020-06-02
plugin id118615
published2018-11-02
reporterThis script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/118615
titleF5 Networks BIG-IP : BIG-IP tmsh vulnerability (K01067037)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from F5 Networks BIG-IP Solution K01067037.
#
# The text description of this plugin is (C) F5 Networks.
#

include("compat.inc");

if (description)
{
  script_id(118615);
  script_version("1.3");
  script_cvs_date("Date: 2019/01/04 10:03:41");

  script_cve_id("CVE-2018-15321");

  script_name(english:"F5 Networks BIG-IP : BIG-IP tmsh vulnerability (K01067037)");
  script_summary(english:"Checks the BIG-IP version.");

  script_set_attribute(
    attribute:"synopsis", 
    value:"The remote device is missing a vendor-supplied security patch."
  );
  script_set_attribute(
    attribute:"description", 
    value:
"When BIG-IP is licensed for Appliance mode, Admin and Resource
administrator roles can by-pass BIG-IP Appliance mode restrictions to
overwrite critical system files. (CVE-2018-15321)

Attackers with ahigh-privilege level can overwrite critical system
files, which in turnbypasses security controls thatlimit TMOS Shell (
tmsh ) commands.This scenario is possible when the Administrator
orResource Administrator roles are granted tmsh access.Resource
Administrator roles must have tmsh access to perform this attack.

Note : F5 does not consider the capability of Advanced Shell ( bash )
access in this vulnerability, as users granted that level of access
can simply perform any command as root. This vulnerability is an issue
for Appliance mode, users who are granted tmsh access, and for the
Resource Administrator role when operating in standard, non-Appliance
mode.

Impact

When the BIG-IP system is licensed for Appliance mode, Administrator
and Resource Administrator roles can by-pass BIG-IP Appliance mode
restrictions to overwrite critical system files."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://support.f5.com/csp/article/K01067037"
  );
  script_set_attribute(
    attribute:"solution", 
    value:
"Upgrade to one of the non-vulnerable versions listed in the F5
Solution K01067037."
  );
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:S/C:N/I:P/A:P");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:H/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"potential_vulnerability", value:"true");
  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_access_policy_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_advanced_firewall_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_acceleration_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_security_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_application_visibility_and_reporting");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_global_traffic_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_link_controller");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_local_traffic_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_policy_enforcement_manager");
  script_set_attribute(attribute:"cpe", value:"cpe:/a:f5:big-ip_webaccelerator");
  script_set_attribute(attribute:"cpe", value:"cpe:/h:f5:big-ip");

  script_set_attribute(attribute:"patch_publication_date", value:"2018/10/30");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_set_attribute(attribute:"plugin_publication_date", value:"2018/11/02");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2018-2019 and is owned by Tenable, Inc. or an Affiliate thereof.");
  script_family(english:"F5 Networks Local Security Checks");

  script_dependencies("f5_bigip_detect.nbin");
  script_require_keys("Host/local_checks_enabled", "Host/BIG-IP/hotfix", "Host/BIG-IP/modules", "Host/BIG-IP/version", "Settings/ParanoidReport");

  exit(0);
}


include("f5_func.inc");

if ( ! get_kb_item("Host/local_checks_enabled") ) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
version = get_kb_item("Host/BIG-IP/version");
if ( ! version ) audit(AUDIT_OS_NOT, "F5 Networks BIG-IP");
if ( isnull(get_kb_item("Host/BIG-IP/hotfix")) ) audit(AUDIT_KB_MISSING, "Host/BIG-IP/hotfix");
if ( ! get_kb_item("Host/BIG-IP/modules") ) audit(AUDIT_KB_MISSING, "Host/BIG-IP/modules");

sol = "K01067037";
vmatrix = make_array();

if (report_paranoia < 2) audit(AUDIT_PARANOID);

# AFM
vmatrix["AFM"] = make_array();
vmatrix["AFM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["AFM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# AM
vmatrix["AM"] = make_array();
vmatrix["AM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["AM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# APM
vmatrix["APM"] = make_array();
vmatrix["APM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["APM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# ASM
vmatrix["ASM"] = make_array();
vmatrix["ASM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["ASM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# AVR
vmatrix["AVR"] = make_array();
vmatrix["AVR"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["AVR"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# GTM
vmatrix["GTM"] = make_array();
vmatrix["GTM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["GTM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# LC
vmatrix["LC"] = make_array();
vmatrix["LC"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["LC"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# LTM
vmatrix["LTM"] = make_array();
vmatrix["LTM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["LTM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# PEM
vmatrix["PEM"] = make_array();
vmatrix["PEM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["PEM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");

# WAM
vmatrix["WAM"] = make_array();
vmatrix["WAM"]["affected"  ] = make_list("14.0.0","13.0.0-13.1.0","12.1.0-12.1.3","11.6.0-11.6.3","11.2.1-11.5.6");
vmatrix["WAM"]["unaffected"] = make_list("14.1.0","14.0.0.3","13.1.0.6","12.1.3.6","11.6.3.3","11.5.7");


if (bigip_is_affected(vmatrix:vmatrix, sol:sol))
{
  if (report_verbosity > 0) security_warning(port:0, extra:bigip_report_get());
  else security_warning(0);
  exit(0);
}
else
{
  tested = bigip_get_tested_modules();
  audit_extra = "For BIG-IP module(s) " + tested + ",";
  if (tested) audit(AUDIT_INST_VER_NOT_VULN, audit_extra, version);
  else audit(AUDIT_HOST_NOT, "running any of the affected modules");
}

References