Vulnerabilities > CVE-2019-19151 - Improper Privilege Management vulnerability in F5 products

047910
CVSS 5.5 - MEDIUM
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
HIGH
Integrity impact
NONE
Availability impact
NONE
local
low complexity
f5
CWE-269
nessus
NVD
Published: 2019-12-23
Updated: 2019-12-31

Summary

On BIG-IP versions 15.0.0-15.1.0, 14.0.0-14.1.2.3, 13.1.0-13.1.3.2, 12.1.0-12.1.5, and 11.5.2-11.6.5.1, BIG-IQ versions 7.0.0, 6.0.0-6.1.0, and 5.0.0-5.4.0, iWorkflow version 2.3.0, and Enterprise Manager version 3.1.1, authenticated users granted TMOS Shell (tmsh) privileges are able access objects on the file system which would normally be disallowed by tmsh restrictions. This allows for authenticated, low privileged attackers to access objects on the file system which would not normally be allowed.

Vulnerable Configurations

Part Description Count
Application
F5
1312

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_SOL21711352.NASL
descriptionAuthenticated users granted TMOS Shell ( tmsh ) privileges can access objects on the file system, which would normally be disallowed by tmsh restrictions. This allows for authenticated, low privileged attackers to access objects on the file system, which would not normally be allowed. (CVE-2019-19151) Note : This vulnerability exists because of an incomplete fix for CVE-2018-5516. Impact This vulnerability allows unauthorized privileges to authenticated administrative users with TMOS Shell ( tmsh) access.
last seen2020-05-08
modified2020-05-01
plugin id136208
published2020-05-01
reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/136208
titleF5 Networks BIG-IP : TMOS Shell vulnerability (K21711352)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were
# extracted from F5 Networks BIG-IP Solution K21711352.
#
# The text description of this plugin is (C) F5 Networks.
#

include("compat.inc");

if (description)
{
  script_id(136208);
  script_version("1.6");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/07/20");

  script_cve_id("CVE-2018-5516", "CVE-2019-19151");

  script_name(english:"F5 Networks BIG-IP : TMOS Shell vulnerability (K21711352)");
  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:
"Authenticated users granted TMOS Shell ( tmsh ) privileges can access
objects on the file system, which would normally be disallowed by tmsh
restrictions. This allows for authenticated, low privileged attackers
to access objects on the file system, which would not normally be
allowed. (CVE-2019-19151)

Note : This vulnerability exists because of an incomplete fix for
CVE-2018-5516.

Impact

This vulnerability allows unauthorized privileges to authenticated
administrative users with TMOS Shell ( tmsh) access."
  );
  script_set_attribute(
    attribute:"see_also",
    value:"https://support.f5.com/csp/article/K21711352"
  );
  script_set_attribute(
    attribute:"solution",
    value:
"Upgrade to one of the non-vulnerable versions listed in the F5
Solution K21711352."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:N/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:N/A:N");
  script_set_cvss3_temporal_vector("CVSS:3.0/E:U/RL:O/RC:C");
  script_set_attribute(attribute:"cvss_score_source", value:"CVE-2018-5516");
  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  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:"vuln_publication_date", value:"2018/05/02");
  script_set_attribute(attribute:"patch_publication_date", value:"2019/12/20");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/05/01");
  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:"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 = "K21711352";
vmatrix = make_array();

if (report_paranoia < 2) audit(AUDIT_PARANOID);

# AFM
vmatrix["AFM"] = make_array();
vmatrix["AFM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["AFM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# AM
vmatrix["AM"] = make_array();
vmatrix["AM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["AM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# APM
vmatrix["APM"] = make_array();
vmatrix["APM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["APM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# ASM
vmatrix["ASM"] = make_array();
vmatrix["ASM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["ASM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# AVR
vmatrix["AVR"] = make_array();
vmatrix["AVR"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["AVR"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# GTM
vmatrix["GTM"] = make_array();
vmatrix["GTM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["GTM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# LC
vmatrix["LC"] = make_array();
vmatrix["LC"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["LC"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# LTM
vmatrix["LTM"] = make_array();
vmatrix["LTM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["LTM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# PEM
vmatrix["PEM"] = make_array();
vmatrix["PEM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["PEM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");

# WAM
vmatrix["WAM"] = make_array();
vmatrix["WAM"]["affected"  ] = make_list("15.1.0","15.0.0","14.0.0-14.1.2","13.0.0-13.1.3","12.1.0-12.1.5","11.5.1-11.6.5");
vmatrix["WAM"]["unaffected"] = make_list("16.0.0","14.1.2.4","13.1.3.4","12.1.5.2");


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