CVE-2020-1738 is a low-severity (CVSS 3.9) CWE-88 vulnerability in ansible. No vendor fix is recorded yet; mitigation options are listed below.
Argument Injection in Ansible
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2020-1738 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,738 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Counts from FIRST.org, log-scaled.
Real-World Exposure
ansible🐍ansible🐍ansibleReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects PyPI packages — download data is not available via public APIs for these ecosystems.
Description
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.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | ansible | all versions | No fix |
| 🐍PyPI | ansible | ≥ 2.8.0a1 | No fix |
| 🐍PyPI | ansible | ≥ 2.9.0a1 | No fix |
Affected Products
ansibleredhatansible towerredhatcloudforms management engineredhatopenstackredhatDetection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for ansible, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Remediation status
No patched version of ansible has shipped for CVE-2020-1738 yet. Where your build allows, override or pin the dependency away from the vulnerable range, and apply any maintainer-recommended mitigation.
Mitigate without a patch
If you can't upgrade right away: gate or disable the affected feature, validate untrusted input at the boundary, and avoid passing attacker-controlled data into the vulnerable path. O3's runtime protection blocks exploitation in production as an interim safeguard until the upgrade lands.
Fixing This On Your OS
If you run this on a Linux distribution, patch through your package manager against the distro's own security advisory below — it tracks the exact backported fix for your release, which can ship on a different timeline (and sometimes a different severity) than the upstream project.
Ansible Engine 2.7.16, 2.8.10, and 2.9.6 as well as previous versions are affected. Ansible Tower 3.4.5, 3.5.5 and 3.6.3 as well as previous versions are affected. In Red Hat OpenStack Platform, because the flaw has a lower impact, ansible is not directly customer exposed, and the fix would require a substantial…
Specify the parameter 'use' when possible on the package and service modules. Avoid using Ansible Collections on Ansible 2.8.9 or 2.7.16 (and any of the previous versions) as they are not rejecting python with no path (already fixed in 2.9.x).Source: Red Hat security advisory for CVE-2020-1738 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Tower 3.4 for RHEL 7 | ansible-tower-34/ansible-tower-memcached:1.4.15-28 | RHBA-2020:0547 |
| Red Hat Ansible Tower 3.5 for RHEL 7 | ansible-tower-35/ansible-tower:3.5.6-1 | RHBA-2020:1539 |
Frequently Asked Questions
Is CVE-2020-1738 in your dependencies?
Find it across PyPI, including transitive dependencies.