CVE-2020-1738: Ansible Argument Injection Vulnerability

LOW
Advisory Identifier: GHSA-f85h-23mf-2fwh
CVSS 3.9
CWE-88
Published
Advisory Summary

CVE-2020-1738 is a LOW (CVSS 3.9) argument injection vulnerability (CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')) affecting Ansible libraries in the PyPI ecosystem. The issue involves argument injection in ansible. Remediation is available in the latest vendor maintenance releases.

CVE-2020-1738 at a Glance

CVE Identifier CVE-2020-1738
GHSA Identifier GHSA-f85h-23mf-2fwh
Severity LOW
CVSS v3.1 Base Score 3.9
CWE Classification CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection')
Affected Product Ansible
Package Ecosystem PyPI
Published Date
Last Updated

Security Impact

CVSS: 3.9

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:N/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 None (C:N)
Integrity Low (I:L)
Availability Low (A:L)

How to Fix CVE-2020-1738

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: Latest secure release
pip install ansible>=Latest secure release
ansible fixed: Latest secure release
pip install ansible>=Latest secure release
ansible fixed: Latest secure release
pip install ansible>=Latest secure release
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-2020-1738, 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 the patched release), 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-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection'), where the product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string. 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 flaw was found in Ansible Engine when the module package or service is used and the parameter 'use' is not specified. If a previous task is executed with a malicious user, the module sent can be selected by the attacker using the ansible facts file. All versions in 2.7.x, 2.8.x and 2.9.x branches are believed to be vulnerable.

CVE-2020-1738 Affected Ansible Versions

3 component(s)
Product / Package Ecosystem Affected Versions Fixed Version
ansible
PyPI
≤ 2.7.16
ansible
PyPI
≥ 2.8.0a1
≤ 2.8.10
ansible
PyPI
≥ 2.9.0a1
≤ 2.9.6

References

Frequently Asked Questions

What is CVE-2020-1738?
CVE-2020-1738 is a security vulnerability in Ansible involving Argument Injection in Ansible under CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection').
Which Ansible versions are affected?
Affected versions include releases prior to current release patches across affected packages: ansible.
What version fixes CVE-2020-1738?
Upgrading to current release patches (or the latest patched release for your respective branch) resolves the vulnerability.
Is ansible affected?
Yes, ansible is affected in releases prior to Latest secure release. Upgrade your dependency to Latest secure release or later.
What is the CVSS score of CVE-2020-1738?
CVE-2020-1738 has a CVSS v3.1 base score of 3.9 (LOW) with vector string CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:L/A:L.
What CWE is associated with CVE-2020-1738?
CVE-2020-1738 is classified under CWE-88: Improper Neutralization of Argument Delimiters in a Command ('Argument Injection') (The product constructs a string for a command to be executed by a separate component in another control sphere, but it does not properly delimit the intended arguments, options, or switches within that command string.).
How can I check PyPI dependencies for CVE-2020-1738?
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
{
  "schema_version" : "1.4.0",
  "id" : "GHSA-f85h-23mf-2fwh",
  "modified" : "2024-09-06T18:18:14Z",
  "published" : "2022-02-09T22:00:04Z",
  "aliases" : [ "CVE-2020-1738" ],
  "summary" : "Argument Injection in Ansible",
  "details" : "A flaw was found in Ansible Engine when the module package or service is used and the parameter 'use' is not specified. If a previous task is executed with a malicious user, the module sent can be selected by the attacker using the ansible facts file. All versions in 2.7.x, 2.8.x and 2.9.x branches are believed to be vulnerable.",
  "severity" : [ {
    "type" : "CVSS_V3",
    "score" : "CVSS:3.1/AV:L/AC:H/PR:L/UI:R/S:C/C:N/I:L/A:L"
  }, {
    "type" : "CVSS_V4",
    "score" : "CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:N/VI:N/VA:N/SC:N/SI:L/SA:L"
  } ],
  "affected" : [ {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "0"
      }, {
        "last_affected" : "2.7.16"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.8.0a1"
      }, {
        "last_affected" : "2.8.10"
      } ]
    } ]
  }, {
    "package" : {
      "ecosystem" : "PyPI",
      "name" : "ansible"
    },
    "ranges" : [ {
      "type" : "ECOSYSTEM",
      "events" : [ {
        "introduced" : "2.9.0a1"
      }, {
        "last_affected" : "2.9.6"
      } ]
    } ]
  } ],
  "references" : [ {
    "type" : "ADVISORY",
    "url" : "https://nvd.nist.gov/vuln/detail/CVE-2020-1738"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/issues/67796"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/ansible/ansible/pull/67808"
  }, {
    "type" : "WEB",
    "url" : "https://bugzilla.redhat.com/show_bug.cgi?id=CVE-2020-1738"
  }, {
    "type" : "ADVISORY",
    "url" : "https://github.com/advisories/GHSA-f85h-23mf-2fwh"
  }, {
    "type" : "PACKAGE",
    "url" : "https://github.com/ansible/ansible"
  }, {
    "type" : "WEB",
    "url" : "https://github.com/pypa/advisory-database/tree/main/vulns/ansible/PYSEC-2020-10.yaml"
  }, {
    "type" : "WEB",
    "url" : "https://security.gentoo.org/glsa/202006-11"
  } ],
  "database_specific" : {
    "cwe_ids" : [ "CWE-88" ],
    "severity" : "LOW",
    "github_reviewed" : true,
    "github_reviewed_at" : "2021-04-05T18:34:03Z",
    "nvd_published_at" : "2020-03-16T16:15:00Z"
  }
}