Vulnerabilities > CVE-2016-5026 - Improper Access Control vulnerability in Onionshare

047910
CVSS 5.5 - MEDIUM
Attack vector
LOCAL
Attack complexity
LOW
Privileges required
LOW
Confidentiality impact
NONE
Integrity impact
HIGH
Availability impact
NONE
local
low complexity
onionshare
CWE-284
nessus
NVD
Published: 2017-01-30
Updated: 2017-02-08

Summary

hs.py in OnionShare before 0.9.1 allows local users to modify the hiddenservice by pre-creating the /tmp/onionshare directory.

Vulnerable Configurations

Part Description Count
Application
Onionshare
10

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • 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.
  • Signature Spoofing by Key Theft
    An attacker obtains an authoritative or reputable signer's private signature key by theft and then uses this key to forge signatures from the original signer to mislead a victim into performing actions that benefit the attacker.

Nessus

  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-CDF8277947.NASL
    descriptionUpdate to 0.9.1 Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-05
    modified2017-01-16
    plugin id96505
    published2017-01-16
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96505
    titleFedora 24 : onionshare (2017-cdf8277947)
    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 FEDORA-2017-cdf8277947.
#

include("compat.inc");

if (description)
{
  script_id(96505);
  script_version("3.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-5026");
  script_xref(name:"FEDORA", value:"2017-cdf8277947");

  script_name(english:"Fedora 24 : onionshare (2017-cdf8277947)");
  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:
"Update to 0.9.1

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
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://bodhi.fedoraproject.org/updates/FEDORA-2017-cdf8277947"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected onionshare package."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:onionshare");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:24");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/01/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/01/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/01/16");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2020 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 = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^24([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 24", "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:"FC24", reference:"onionshare-0.9.1-1.fc24")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "onionshare");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2017-E6A9108CCE.NASL
    descriptionUpdate to 0.9.1 Note that Tenable Network Security has extracted the preceding description block directly from the Fedora update system website. Tenable has attempted to automatically clean and format it as much as possible without introducing additional issues.
    last seen2020-06-05
    modified2017-01-16
    plugin id96506
    published2017-01-16
    reporterThis script is Copyright (C) 2017-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/96506
    titleFedora 25 : onionshare (2017-e6a9108cce)
    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 FEDORA-2017-e6a9108cce.
#

include("compat.inc");

if (description)
{
  script_id(96506);
  script_version("3.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2016-5026");
  script_xref(name:"FEDORA", value:"2017-e6a9108cce");

  script_name(english:"Fedora 25 : onionshare (2017-e6a9108cce)");
  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:
"Update to 0.9.1

Note that Tenable Network Security has extracted the preceding
description block directly from the Fedora update system website.
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://bodhi.fedoraproject.org/updates/FEDORA-2017-e6a9108cce"
  );
  script_set_attribute(
    attribute:"solution", 
    value:"Update the affected onionshare package."
  );
  script_set_cvss_base_vector("CVSS2#AV:L/AC:L/Au:N/C:N/I:P/A:N");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:H/A:N");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:onionshare");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:25");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/01/30");
  script_set_attribute(attribute:"patch_publication_date", value:"2017/01/14");
  script_set_attribute(attribute:"plugin_publication_date", value:"2017/01/16");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2017-2020 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 = pregmatch(pattern: "Fedora.*release ([0-9]+)", string:release);
if (isnull(os_ver)) audit(AUDIT_UNKNOWN_APP_VER, "Fedora");
os_ver = os_ver[1];
if (! preg(pattern:"^25([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 25", "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:"FC25", reference:"onionshare-0.9.1-1.fc25")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_NOTE,
    extra      : rpm_report_get()
  );
  exit(0);
}
else
{
  tested = pkg_tests_get();
  if (tested) audit(AUDIT_PACKAGE_NOT_AFFECTED, tested);
  else audit(AUDIT_PACKAGE_NOT_INSTALLED, "onionshare");
}

References