CVE-2020-1733: Ansible Remote Code Execution Vulnerability

LOW
Advisory Identifier: GHSA-g4mq-6fp5-qwcf
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CVSS 5.0
CWE-668 CWE-362 CWE-377
Published
Advisory Summary

CVE-2020-1733 is a LOW (CVSS 5.0) remote code execution vulnerability (CWE-668: Exposure of Resource to Wrong Sphere) affecting Ansible libraries in the PyPI ecosystem. The issue involves ansible vulnerable to exposure of resource to wrong sphere and insecure temporary file. Remediation is available by upgrading affected packages to version 2.7.17, 2.8.11, 2.9.7.

CVE-2020-1733 at a Glance

CVE Identifier CVE-2020-1733
GHSA Identifier GHSA-g4mq-6fp5-qwcf
Severity LOW
CVSS v3.1 Base Score 5.0
CWE Classification CWE-668: Exposure of Resource to Wrong Sphere
Affected Product Ansible
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 5.0

The security impact metrics below are parsed directly from the CVSS v3.1 vector string (CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L).

Attack Vector Local (AV:L)
Attack Complexity High (AC:H)
Privileges Required Low (PR:L)
User Interaction Required (UI:R)
Scope Changed (S:C)
Confidentiality Low (C:L)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2020-1733

To remediate this vulnerability, upgrade all affected Ansible dependencies to a patched release. Both direct and transitive dependencies should be checked, as frameworks or security libraries may pull in vulnerable versions transitively.

ansible fixed: 2.7.17 
pip install ansible>=2.7.17
ansible fixed: 2.8.11 
pip install ansible>=2.8.11
ansible fixed: 2.9.7 
pip install ansible>=2.9.7
Verify Direct and Transitive Dependencies

Run the following command in your project directory to verify that all resolved dependencies use the patched release: 

pip show ansible

How to Check if You Are Affected

To determine whether your Python environment is affected by CVE-2020-1733, inspect your installed packages using pip:

pip show ansible

Analyze the terminal output to locate any version of Ansible in your dependency tree. If any resolved version matches the vulnerable ranges listed in the table below (for example, versions earlier than 2.7.17), your application is affected.

Note: The pip show ansible command checks currently installed packages in your active Python environment.

Technical Details

Vulnerability Mechanism & Technical Analysis

This vulnerability is classified under CWE-668: Exposure of Resource to Wrong Sphere, where the product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource. In Ansible, software state validation or input boundaries are circumvented during processing. Review the official source advisory statement below for specific affected components, classes, and reproduction details.

Source Advisory Statement

A race condition flaw was found in Ansible Engine 2.7.17 and prior, 2.8.9 and prior, 2.9.6 and prior when running a playbook with an unprivileged become user. When Ansible needs to run a module with become user, the temporary directory is created in /var/tmp. This directory is created with "umask 77 && mkdir -p <dir>"; this operation does not fail if the directory already exists and is owned by another user. An attacker could take advantage to gain control of the become user as the target directory can be retrieved by iterating '/proc/<pid>/cmdline'.

CVE-2020-1733 Affected Ansible Versions

3 component(s)
Fixed Versions:
2.7.172.8.112.9.7
Product / Package Ecosystem Affected Versions Fixed Version
ansible
pypi/ansible
PyPI
< 2.7.17
2.7.17
ansible
pypi/ansible
PyPI
≥ 2.8.0a1
< 2.8.11
2.8.11
ansible
pypi/ansible
PyPI
≥ 2.9.0a1
< 2.9.7
2.9.7

References

NVD — CVE-2020-1733 NVD
https://nvd.nist.gov/vuln/detail/CVE-2020-1733
Ansible Source Repository REPOSITORY
https://github.com/ansible/ansible/issues/67791
Security Fix Commit FIX COMMIT
https://github.com/ansible/ansible/commit/80b9a0a25c5f75e84aefc8f2b293fb1933b154f2
Security Fix Commit FIX COMMIT
https://github.com/ansible/ansible/commit/8251d9f4c2bc82632ab992277fcd30ccbf87aa47
Security Fix Commit FIX COMMIT
https://github.com/ansible/ansible/commit/ecf99d5e1ff732a7777010facd6c98bb0994605e
bugzilla.redhat.com/show_bug.cgi WEB
https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1733
GitHub Advisory / Wiki ADVISORY
https://github.com/advisories/GHSA-g4mq-6fp5-qwcf
Ansible Source Repository REPOSITORY
https://github.com/ansible/ansible
Ansible Source Repository REPOSITORY
https://github.com/pypa/advisory-database/tree/main/vulns/ansible/PYSEC-2020-5.yaml
lists.debian.org/debian-lts-announce... WEB
https://lists.debian.org/debian-lts-announce/2020/05/msg00005.html
Ansible Security Information SECURITY
https://security.gentoo.org/glsa/202006-11
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DKPA4KC3OJSUFASUYMG66HKJE7ADNGFW
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MRRYUU5ZBLPBXCYG6CFP35D64NP2UB2S
lists.fedoraproject.org/archives/list/packa... WEB
https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WQVOQD4VAIXXTVQAJKTN7NUGTJFE2PCB
Ansible Security Information SECURITY
https://www.debian.org/security/2021/dsa-4950

Frequently Asked Questions

What is CVE-2020-1733?
CVE-2020-1733 is a security vulnerability in Ansible involving Ansible vulnerable to Exposure of Resource to Wrong Sphere and Insecure Temporary File under CWE-668: Exposure of Resource to Wrong Sphere.
Which Ansible versions are affected?
Affected versions include releases prior to 2.7.17, 2.8.11, 2.9.7 across affected packages: ansible.
What version fixes CVE-2020-1733?
Upgrading to 2.7.17, 2.8.11, 2.9.7 (or the latest patched release for your respective branch) resolves the vulnerability.
Is ansible affected?
Yes, ansible is affected in releases prior to 2.7.17, 2.8.11, 2.9.7. Upgrade your dependency to 2.7.17, 2.8.11, 2.9.7 or later.
What is the CVSS score of CVE-2020-1733?
CVE-2020-1733 has a CVSS v3.1 base score of 5.0 (LOW) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L.
What CWE is associated with CVE-2020-1733?
CVE-2020-1733 is classified under CWE-668: Exposure of Resource to Wrong Sphere (The product exposes a resource to the wrong control sphere, providing unintended actors with inappropriate access to the resource.).
How can I check PyPI dependencies for CVE-2020-1733?
Run the dependency tree command: 'pip show ansible'. This command lists direct and transitive dependencies in your build configuration so you can verify if a vulnerable version is resolved.
Machine-readable OSV JSON OSV v1.5 Schema
Normalized schema output
View Raw JSON 
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-g4mq-6fp5-qwcf",
  "modified" : "2024-11-18T16:26:12Z",
  "published" : "2021-04-20T16:46:12Z",
  "aliases" : [ "CVE-2020-1733" ],
  "summary" : "Ansible vulnerable to Exposure of Resource to Wrong Sphere and Insecure Temporary File",
  "details" : "A race condition flaw was found in Ansible Engine 2.7.17 and prior, 2.8.9 and prior, 2.9.6 and prior when running a playbook with an unprivileged become user. When Ansible needs to run a module with become user, the temporary directory is created in /var/tmp. This directory is created with \"umask 77 && mkdir -p <dir>\"; this operation does not fail if the directory already exists and is owned by another user. An attacker could take advantage to gain control of the become user as the target directory can be retrieved by iterating '/proc/<pid>/cmdline'.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:L/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:L/VI:L/VA:L/SC:L/SI:L/SA:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "fixed" : "2.7.17"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.8.0a1"
      }, {
        "fixed" : "2.8.11"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.9.0a1"
      }, {
        "fixed" : "2.9.7"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-1733"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/issues/67791"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/commit/80b9a0a25c5f75e84aefc8f2b293fb1933b154f2"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/commit/8251d9f4c2bc82632ab992277fcd30ccbf87aa47"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/commit/ecf99d5e1ff732a7777010facd6c98bb0994605e"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1733"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-g4mq-6fp5-qwcf"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ansible/ansible"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/ansible/PYSEC-2020-5.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://lists.debian.org/debian-lts-announce/2020/05/msg00005.html"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/DKPA4KC3OJSUFASUYMG66HKJE7ADNGFW"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/MRRYUU5ZBLPBXCYG6CFP35D64NP2UB2S"
  }, {
    "type" : "WEB",
    "url" : "https://lists.fedoraproject.org/archives/list/package-announce@lists.fedoraproject.org/message/WQVOQD4VAIXXTVQAJKTN7NUGTJFE2PCB"
  }, {
    "type" : "WEB",
    "url" : "https://security.gentoo.org/glsa/202006-11"
  }, {
    "type" : "WEB",
    "url" : "https://www.debian.org/security/2021/dsa-4950"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-362", "CWE-377", "CWE-668" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-05T18:50:43Z",
    "nvd_published_at" : "2020-03-11T19:15:00Z"
  }
}