Vulnerabilities > CVE-2019-15608 - Time-of-check Time-of-use (TOCTOU) Race Condition vulnerability in Yarnpkg Yarn

047910
CVSS 5.9 - MEDIUM
Attack vector
NETWORK
Attack complexity
HIGH
Privileges required
NONE
Confidentiality impact
NONE
Integrity impact
HIGH
Availability impact
NONE
network
high complexity
yarnpkg
CWE-367
nessus
NVD
Published: 2020-03-15
Updated: 2020-03-21

Summary

The package integrity validation in yarn < 1.19.0 contains a TOCTOU vulnerability where the hash is computed before writing a package to cache. It's not computed again when reading from the cache. This may lead to a cache pollution attack.

Vulnerable Configurations

Part Description Count
Application
Yarnpkg
130

Common Weakness Enumeration (CWE)

Common Attack Pattern Enumeration and Classification (CAPEC)

  • Leveraging Race Conditions via Symbolic Links
    This attack leverages the use of symbolic links (Symlinks) in order to write to sensitive files. An attacker can create a Symlink link to a target file not otherwise accessible to her. When the privileged program tries to create a temporary file with the same name as the Symlink link, it will actually write to the target file pointed to by the attackers' Symlink link. If the attacker can insert malicious content in the temporary file she will be writing to the sensitive file by using the Symlink. The race occurs because the system checks if the temporary file exists, then creates the file. The attacker would typically create the Symlink during the interval between the check and the creation of the temporary 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 familyPhotonOS Local Security Checks
    NASL idPHOTONOS_PHSA-2020-1_0-0288_YARN.NASL
    descriptionAn update of the yarn package has been released.
    last seen2020-04-22
    modified2020-04-15
    plugin id135493
    published2020-04-15
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/135493
    titlePhoton OS 1.0: Yarn PHSA-2020-1.0-0288
    code
    #
# (C) Tenable Network Security, Inc.
#


# The descriptive text and package checks in this plugin were
# extracted from VMware Security Advisory PHSA-2020-1.0-0288. The text
# itself is copyright (C) VMware, Inc.


include('compat.inc');

if (description)
{
  script_id(135493);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/21");

  script_cve_id("CVE-2019-15608");

  script_name(english:"Photon OS 1.0: Yarn PHSA-2020-1.0-0288");

  script_set_attribute(attribute:"synopsis", value:
"The remote PhotonOS host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"An update of the yarn package has been released.");
  script_set_attribute(attribute:"see_also", value:"https://github.com/vmware/photon/wiki/Security-Updates-1.0-288.md");
  script_set_attribute(attribute:"solution", value:
"Update the affected Linux packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/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-2019-15608");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/03/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/04/11");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/15");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:vmware:photonos:yarn");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:vmware:photonos:1.0");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"PhotonOS Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/PhotonOS/release", "Host/PhotonOS/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/PhotonOS/release");
if (isnull(release) || release !~ "^VMware Photon") audit(AUDIT_OS_NOT, "PhotonOS");
if (release !~ "^VMware Photon (?:Linux|OS) 1\.0(\D|$)") audit(AUDIT_OS_NOT, "PhotonOS 1.0");

if (!get_kb_item("Host/PhotonOS/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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "PhotonOS", cpu);

flag = 0;

if (rpm_exists(rpm:"yarn-1.10", release:"PhotonOS-1.0") && rpm_check(release:"PhotonOS-1.0", cpu:"x86_64", reference:"yarn-1.10.1-6.ph1")) 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, "yarn");
}
  • NASL familyPhotonOS Local Security Checks
    NASL idPHOTONOS_PHSA-2020-3_0-0078_YARN.NASL
    descriptionAn update of the yarn package has been released.
    last seen2020-04-30
    modified2020-04-21
    plugin id135786
    published2020-04-21
    reporterThis script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.
    sourcehttps://www.tenable.com/plugins/nessus/135786
    titlePhoton OS 3.0: Yarn PHSA-2020-3.0-0078
    code
    #
# (C) Tenable Network Security, Inc.
#


# The descriptive text and package checks in this plugin were
# extracted from VMware Security Advisory PHSA-2020-3.0-0078. The text
# itself is copyright (C) VMware, Inc.


include('compat.inc');

if (description)
{
  script_id(135786);
  script_version("1.2");
  script_set_attribute(attribute:"plugin_modification_date", value:"2020/04/23");

  script_cve_id("CVE-2019-15608");

  script_name(english:"Photon OS 3.0: Yarn PHSA-2020-3.0-0078");

  script_set_attribute(attribute:"synopsis", value:
"The remote PhotonOS host is missing multiple security updates.");
  script_set_attribute(attribute:"description", value:
"An update of the yarn package has been released.");
  script_set_attribute(attribute:"see_also", value:"https://github.com/vmware/photon/wiki/Security-Updates-3.0-78.md");
  script_set_attribute(attribute:"solution", value:
"Update the affected Linux packages.");
  script_set_cvss_base_vector("CVSS2#AV:N/AC:M/Au:N/C:N/I:P/A:N");
  script_set_cvss_temporal_vector("CVSS2#E:U/RL:OF/RC:C");
  script_set_cvss3_base_vector("CVSS:3.0/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/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-2019-15608");

  script_set_attribute(attribute:"exploitability_ease", value:"No known exploits are available");

  script_set_attribute(attribute:"vuln_publication_date", value:"2020/03/15");
  script_set_attribute(attribute:"patch_publication_date", value:"2020/04/08");
  script_set_attribute(attribute:"plugin_publication_date", value:"2020/04/21");

  script_set_attribute(attribute:"plugin_type", value:"local");
  script_set_attribute(attribute:"cpe", value:"p-cpe:/a:vmware:photonos:yarn");
  script_set_attribute(attribute:"cpe", value:"cpe:/o:vmware:photonos:3.0");
  script_end_attributes();

  script_category(ACT_GATHER_INFO);
  script_family(english:"PhotonOS Local Security Checks");

  script_copyright(english:"This script is Copyright (C) 2020 and is owned by Tenable, Inc. or an Affiliate thereof.");

  script_dependencies("ssh_get_info.nasl");
  script_require_keys("Host/local_checks_enabled", "Host/PhotonOS/release", "Host/PhotonOS/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/PhotonOS/release");
if (isnull(release) || release !~ "^VMware Photon") audit(AUDIT_OS_NOT, "PhotonOS");
if (release !~ "^VMware Photon (?:Linux|OS) 3\.0(\D|$)") audit(AUDIT_OS_NOT, "PhotonOS 3.0");

if (!get_kb_item("Host/PhotonOS/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$" && "aarch64" >!< cpu) audit(AUDIT_LOCAL_CHECKS_NOT_IMPLEMENTED, "PhotonOS", cpu);

flag = 0;

if (rpm_check(release:"PhotonOS-3.0", reference:"yarn-1.10.1-8.ph3")) 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, "yarn");
}

References