CVE-2021-20191 is a medium-severity (CVSS 5.5) CWE-532 vulnerability in ansible. A fix is available for ansible — see the affected versions and patch details below.
Insertion of Sensitive Information into Log File in ansible
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
CVE-2021-20191 by exploitation likelihood (EPSS) against impact (CVSS). Outside the shaded patch-first corner.
Where this sits among everything scored
Of 385,386 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. Credentials, such as secrets, are being disclosed in console log by default and not protected by no_log feature when using those modules. An attacker can take advantage of this information to steal those credentials. The highest threat from this vulnerability is to data confidentiality. Versions before ansible 2.9.18 are affected.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| 🐍PyPI | ansible | ≥ 2.9.0a1&&< 2.9.18rc1 | 2.9.18rc1pip install --upgrade 'ansible==2.9.18rc1' |
| 🐍PyPI | ansible | all versions | 2.8.19rc1pip install --upgrade 'ansible==2.8.19rc1' |
| 🐍PyPI | ansible | ≥ 2.10.0a1&&< 2.10.7 | 2.10.7pip install --upgrade 'ansible==2.10.7' |
Affected Products
virtualizationoracleansibleredhatansible towerredhatcisco nx-os collectionredhatcommunity general collectionredhatcommunity network collectionredhatDetection & 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.
Fix
Update ansible to 2.9.18rc1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-20191 is resolved across your whole dependency graph.
Workarounds
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.
The version of ansible shipped with Red Hat Gluster Storage (RHGS) 3 includes the vulnerable `network/nxos/nxos_*` modules. However, RHGS 3 no longer maintains its own version of Ansible, prerequisite is to enable ansible repository in order to consume the latest version of ansible which has many bug and security…
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Ansible Automation Platform 1.2 for RHEL 7 | ansible-automation-platform/platform-resource-operator-bundle:v0.1.1-1 | RHSA-2021:1079 |
| Red Hat Ansible Engine 2.9 for RHEL 7 | ansible-0:2.9.18-1.el7ae | RHSA-2021:0664 |
| Red Hat Ansible Engine 2 for RHEL 7 | ansible-0:2.9.18-1.el7ae | RHSA-2021:0663 |
| Red Hat Virtualization 4 for Red Hat Enterprise Linux 8 | ansible-0:2.9.18-1.el8ae | RHSA-2021:2180 |
Frequently Asked Questions
Is CVE-2021-20191 in your dependencies?
Find it across PyPI, including transitive dependencies.