Vulnerabilities > CVE-2020-8162 - Unrestricted Upload of File with Dangerous Type vulnerability in multiple products

047910
CVSS 5.0 - MEDIUM
Attack vector
NETWORK
Attack complexity
LOW
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
PARTIAL
Availability impact
NONE
network
low complexity
rubyonrails
debian
CWE-434
nessus

Summary

A client side enforcement of server side security vulnerability exists in rails < 5.2.4.2 and rails < 6.0.3.1 ActiveStorage's S3 adapter that allows the Content-Length of a direct file upload to be modified by an end user bypassing upload limits.

Vulnerable Configurations

Part Description Count
Application
Rubyonrails
394
OS
Debian
1

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.

Nessus

NASL familyFreeBSD Local Security Checks
NASL idFREEBSD_PKG_85FCA71899F611EABF1D08002728F74C.NASL
descriptionRuby on Rails blog : Hi everyone! Rails 5.2.4.3 and 6.0.3.1 have been released! These releases contain important security fixes, so please upgrade when you can. Both releases contain the following fixes : CVE-2020-8162: Circumvention of file size limits in ActiveStorage CVE-2020-8164: Possible Strong Parameters Bypass in ActionPack CVE-2020-8165: Potentially unintended unmarshalling of user-provided objects in MemCacheStore and RedisCacheStore CVE-2020-8166: Ability to forge per-form CSRF tokens given a global CSRF token CVE-2020-8167: CSRF Vulnerability in rails-ujs
last seen2020-05-21
modified2020-05-20
plugin id136726
published2020-05-20
reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
sourcehttps://www.tenable.com/plugins/nessus/136726
titleFreeBSD : Rails -- multiple vulnerabilities (85fca718-99f6-11ea-bf1d-08002728f74c)
code
#
# (C) Tenable Network Security, Inc.
#
# The descriptive text and package checks in this plugin were  
# extracted from the FreeBSD VuXML database :
#
# Copyright 2003-2020 Jacques Vidrine and contributors
#
# Redistribution and use in source (VuXML) and 'compiled' forms (SGML,
# HTML, PDF, PostScript, RTF and so forth) with or without modification,
# are permitted provided that the following conditions are met:
# 1. Redistributions of source code (VuXML) must retain the above
#    copyright notice, this list of conditions and the following
#    disclaimer as the first lines of this file unmodified.
# 2. Redistributions in compiled form (transformed to other DTDs,
#    published online in any format, converted to PDF, PostScript,
#    RTF and other formats) must reproduce the above copyright
#    notice, this list of conditions and the following disclaimer
#    in the documentation and/or other materials provided with the
#    distribution.
# 
# THIS DOCUMENTATION IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS"
# AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO,
# THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
# PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS
# BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY,
# OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT
# OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
# BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
# WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
# OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS DOCUMENTATION,
# EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
#

include("compat.inc");

if (description)
{
  script_id(136726);
  script_version("1.3");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/26");

  script_cve_id("CVE-2020-8162", "CVE-2020-8164", "CVE-2020-8165", "CVE-2020-8166", "CVE-2020-8167");

  script_name(english:"FreeBSD : Rails -- multiple vulnerabilities (85fca718-99f6-11ea-bf1d-08002728f74c)");
  script_summary(english:"Checks for updated packages in pkg_info output");

  script_set_attribute(
    attribute:"synopsis",
    value:
"The remote FreeBSD host is missing one or more security-related
updates."
  );
  script_set_attribute(
    attribute:"description",
    value:
"Ruby on Rails blog :

Hi everyone! Rails 5.2.4.3 and 6.0.3.1 have been released! These
releases contain important security fixes, so please upgrade when you
can.

Both releases contain the following fixes :

CVE-2020-8162: Circumvention of file size limits in ActiveStorage

CVE-2020-8164: Possible Strong Parameters Bypass in ActionPack

CVE-2020-8165: Potentially unintended unmarshalling of user-provided
objects in MemCacheStore and RedisCacheStore

CVE-2020-8166: Ability to forge per-form CSRF tokens given a global
CSRF token

CVE-2020-8167: CSRF Vulnerability in rails-ujs"
  );
  # https://weblog.rubyonrails.org/2020/5/18/Rails-5-2-4-3-and-6-0-3-1-have-been-released/
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?8268ac87"
  );
  # https://groups.google.com/forum/#!topic/rubyonrails-security/PjU3946mreQ
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?97c30406"
  );
  # https://groups.google.com/forum/#!topic/rubyonrails-security/f6ioe4sdpbY
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?fc4f9c88"
  );
  # https://groups.google.com/forum/#!topic/rubyonrails-security/bv6fW4S0Y1c
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?bbe96cfa"
  );
  # https://groups.google.com/forum/#!topic/rubyonrails-security/NOjKiGeXUgw
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?62b6f4ce"
  );
  # https://groups.google.com/forum/#!topic/rubyonrails-security/x9DixQDG9a0
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?59fb4e94"
  );
  # https://vuxml.freebsd.org/freebsd/85fca718-99f6-11ea-bf1d-08002728f74c.html
  script_set_attribute(
    attribute:"see_also",
    value:"http://www.nessus.org/u?a6180b1f"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:L/Au:N/C:P/I:P/A:P");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:L/PR:N/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-2020-8165");
  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:freebsd:freebsd:rubygem-actionpack52");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-actionpack60");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-actionview52");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-actionview60");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-activestorage52");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-activestorage60");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-activesupport52");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:freebsd:freebsd:rubygem-activesupport60");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:freebsd:freebsd");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/05/18");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/05/19");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/05/20");
  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:"FreeBSD Local Security Checks");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/FreeBSD/release", "Host/FreeBSD/pkg_info");

  exit(0);
}


include("audit.inc");
include("freebsd_package.inc");


if (!get_kb_item("Host/local_checks_enabled")) audit(AUDIT_LOCAL_CHECKS_NOT_ENABLED);
if (!get_kb_item("Host/FreeBSD/release")) audit(AUDIT_OS_NOT, "FreeBSD");
if (!get_kb_item("Host/FreeBSD/pkg_info")) audit(AUDIT_PACKAGE_LIST_MISSING);


flag = 0;

if (pkg_test(save_report:TRUE, pkg:"rubygem-actionpack52<5.2.4.3")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-actionview52<5.2.4.3")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-activestorage52<5.2.4.3")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-activesupport52<5.2.4.3")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-actionpack60<6.0.3.1")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-actionview60<6.0.3.1")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-activestorage60<6.0.3.1")) flag++;
if (pkg_test(save_report:TRUE, pkg:"rubygem-activesupport60<6.0.3.1")) flag++;

if (flag)
{
  if (report_verbosity > 0) security_hole(port:0, extra:pkg_report_get());
  else security_hole(0);
  exit(0);
}
else audit(AUDIT_HOST_NOT, "affected");