Vulnerabilities > CVE-2015-8239 - Race Condition vulnerability in Sudo Project Sudo

047910
CVSS 6.9 - MEDIUM
Attack vector
LOCAL
Attack complexity
MEDIUM
Privileges required
NONE
Confidentiality impact
COMPLETE
Integrity impact
COMPLETE
Availability impact
COMPLETE
local
sudo-project
CWE-362
nessus
NVD
Published: 2017-10-10
Updated: 2017-11-05

Summary

The SHA-2 digest support in the sudoers plugin in sudo after 1.8.7 allows local users with write permissions to parts of the called command to replace them before it is executed.

Vulnerable Configurations

Part Description Count
Application
Sudo_Project
66

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Leveraging Race Conditions
    This attack targets a race condition occurring when multiple processes access and manipulate the same resource concurrently and the outcome of the execution depends on the particular order in which the access takes place. The attacker can leverage a race condition by "running the race", modifying the resource and modifying the normal execution flow. For instance a race condition can occur while accessing a file, the attacker can trick the system by replacing the original file with his version and cause the system to read the malicious file.
  • Leveraging Time-of-Check and Time-of-Use (TOCTOU) Race Conditions
    This attack targets a race condition occurring between the time of check (state) for a resource and the time of use of a resource. The typical example is the file access. The attacker can leverage a file access race condition by "running the race", meaning that he would modify the resource between the first time the target program accesses the file and the time the target program uses the file. During that period of time, the attacker could do something such as replace the file and cause an escalation of privilege.

Nessus

  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2016-F1E8E27E27.NASL
    description - update to 1.8.17p1 - installs the /var/db/sudo/lectured directory 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
    modified2016-07-18
    plugin id92337
    published2016-07-18
    reporterThis script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/92337
    titleFedora 23 : sudo (2016-f1e8e27e27)
    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-2016-f1e8e27e27.
#

include("compat.inc");

if (description)
{
  script_id(92337);
  script_version("2.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2015-8239");
  script_xref(name:"FEDORA", value:"2016-f1e8e27e27");

  script_name(english:"Fedora 23 : sudo (2016-f1e8e27e27)");
  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 1.8.17p1

  - installs the /var/db/sudo/lectured directory

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-2016-f1e8e27e27"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected sudo package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:sudo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:23");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/10/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/16");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/18");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2020 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:"^23([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 23", "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:"FC23", reference:"sudo-1.8.17p1-1.fc23")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    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, "sudo");
}
  • NASL familyFedora Local Security Checks
    NASL idFEDORA_2016-90836CA57D.NASL
    description - update to 1.8.17p1 - installs the /var/db/sudo/lectured directory 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
    modified2016-07-18
    plugin id92331
    published2016-07-18
    reporterThis script is Copyright (C) 2016-2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/92331
    titleFedora 22 : sudo (2016-90836ca57d)
    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-2016-90836ca57d.
#

include("compat.inc");

if (description)
{
  script_id(92331);
  script_version("2.5");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/06/04");

  script_cve_id("CVE-2015-8239");
  script_xref(name:"FEDORA", value:"2016-90836ca57d");

  script_name(english:"Fedora 22 : sudo (2016-90836ca57d)");
  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 1.8.17p1

  - installs the /var/db/sudo/lectured directory

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-2016-90836ca57d"
  );
  script_set_attribute(attribute:"solution", value:"Update the affected sudo package.");
  script_set_cvss_base_vector("CVSS2#AV:L/AC:M/Au:N/C:C/I:C/A:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:L/AC:H/PR:L/UI:N/S:U/C:H/I:H/A:H");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:fedoraproject:fedora:sudo");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:fedoraproject:fedora:22");

  script_set_attribute(attribute:"vuln_publication_date", value:"2017/10/10");
  script_set_attribute(attribute:"patch_publication_date", value:"2016/07/15");
  script_set_attribute(attribute:"plugin_publication_date", value:"2016/07/18");
  script_set_attribute(attribute:"generated_plugin", value:"current");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_copyright(english:"This script is Copyright (C) 2016-2020 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:"^22([^0-9]|$)", string:os_ver)) audit(AUDIT_OS_NOT, "Fedora 22", "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:"FC22", reference:"sudo-1.8.17p1-1.fc22")) flag++;


if (flag)
{
  security_report_v4(
    port       : 0,
    severity   : SECURITY_WARNING,
    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, "sudo");
}

References