CVE-2021-21642 is a high-severity (CVSS 8.1) XML External Entity (XXE) vulnerability in org.jenkins-ci.plugins:config-file-provider. EPSS puts its 30-day exploitation probability at 37.8% (98th percentile). A fix is available for org.jenkins-ci.plugins:config-file-provider — see the affected versions and patch details below.
XML External Entity Reference vulnerability in Jenkins Config File Provider Plugin
EPSS Exploitation Probability
EPSS (Exploit Prediction Scoring System) is a daily probability model maintained by FIRST.org. It estimates the likelihood a CVE will be exploited in production environments within the next 30 days, derived from real-world threat intelligence signals.
How urgent is this, really
CVE-2021-21642 plotted by exploitation likelihood (EPSS) against impact (CVSS). The shaded corner — EPSS 50%+ and CVSS 7.0+ — is where this CVE doesn't sit, though severity or exploitability alone can still warrant action.
Where this sits among everything scored
Of 379,145 CVEs with a current EPSS score, this one falls in the 10–50% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.jenkins-ci.plugins:config-file-providerReal-time download stats are indexed for npm and PyPI packages. This vulnerability affects Maven packages — download data is not available via public APIs for these ecosystems.
Description
Jenkins Config File Provider Plugin 3.7.0 and earlier does not configure its XML parser to prevent XML external entity (XXE) attacks.
This allows attackers with the ability to define Maven configuration files to have Jenkins parse a crafted configuration file that uses external entities for extraction of secrets from the Jenkins controller or server-side request forgery.
Jenkins Config File Provider Plugin 3.7.1 disables external entity resolution for its XML parser.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.jenkins-ci.plugins:config-file-provider | all versions | 3.7.1org.jenkins-ci.plugins:config-file-provider:3.7.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jenkins-ci.plugins:config-file-provider, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.jenkins-ci.plugins:config-file-provider to 3.7.1 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-21642 is resolved across your whole dependency graph.
Workarounds
Restrict outbound requests from the affected component to an allowlist of hosts, block access to link-local and internal address ranges at the network layer, and require authentication on internal services so a forged request cannot reach them unauthenticated.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2021-21642 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2021-21642. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
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.
Red Hat has investigated whether a possible mitigation exists for this issue, and has not been able to identify a practical example. Please update as soon as possible.Source: Red Hat security advisory for CVE-2021-21642 (CC BY 4.0)
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Migration Toolkit for Containers 1.4 | rhmtc/openshift-migration-controller-rhel8:v1.4.6-4 | RHBA-2021:2854 |
| Red Hat OpenShift Container Platform 3.11 | jenkins-2-plugins-0:3.11.1624366838-1.el7 | RHSA-2021:2517 |
| Red Hat OpenShift Container Platform 4.5 | jenkins-2-plugins-0:4.5.1623326336-1.el7 | RHSA-2021:2431 |
| Red Hat OpenShift Container Platform 4.6 | jenkins-2-plugins-0:4.6.1623162648-1.el8 | RHBA-2021:2407 |
| Red Hat OpenShift Container Platform 4.7 | cri-o-0:1.20.2-12.rhaos4.7.git9f7be76.el7 | RHSA-2021:2122 |
| Red Hat OpenShift Container Platform 4.8 | atomic-openshift-service-idler-0:4.8.0-202106281541.p0.git.39cfc66.assembly.stream.el8 | RHSA-2021:2437 |
Frequently Asked Questions
Is CVE-2021-21642 in your dependencies?
O3 Security finds CVE-2021-21642 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.