CVE-2018-8039 is a high-severity (CVSS 8.1) CWE-755 vulnerability in org.apache.cxf:cxf-rt-transports-http. A fix is available for org.apache.cxf:cxf-rt-transports-http — see the affected versions and patch details below.
Apache CXF TLS hostname verification does not work correctly with com.sun.net.ssl.*
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-2018-8039 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 378,567 CVEs with a current EPSS score, this one falls in the < 10% band (highlighted). Real counts from FIRST.org, not a sample — log-scaled since the landscape is heavily right-skewed.
Real-World Exposure
org.apache.cxf:cxf-rt-transports-http☕org.apache.cxf:cxf-rt-transports-http☕org.apache.cxf:apache-cxf☕org.apache.cxf:apache-cxfReal-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
It is possible to configure Apache CXF to use the com.sun.net.ssl implementation via 'System.setProperty("java.protocol.handler.pkgs", "com.sun.net.ssl.internal.www.protocol");'. When this system property is set, CXF uses some reflection to try to make the HostnameVerifier work with the old com.sun.net.ssl.HostnameVerifier interface. However, the default HostnameVerifier implementation in CXF does not implement the method in this interface, and an exception is thrown. However, in Apache CXF prior to 3.2.5 and 3.1.16 the exception is caught in the reflection code and not properly propagated. What this means is that if you are using the com.sun.net.ssl stack with CXF, an error with TLS hostname verification will not be thrown, leaving a CXF client subject to man-in-the-middle attacks.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.cxf:cxf-rt-transports-http | ≥ 3.2.0&&< 3.2.5 | 3.2.5org.apache.cxf:cxf-rt-transports-http:3.2.5 |
| ☕Maven | org.apache.cxf:cxf-rt-transports-http | all versions | 3.1.16org.apache.cxf:cxf-rt-transports-http:3.1.16 |
| ☕Maven | org.apache.cxf:apache-cxf | ≥ 3.2.0&&< 3.2.5 | 3.2.5org.apache.cxf:apache-cxf:3.2.5 |
| ☕Maven | org.apache.cxf:apache-cxf | all versions | 3.1.16org.apache.cxf:apache-cxf:3.1.16 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.cxf:cxf-rt-transports-http, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.cxf:cxf-rt-transports-http to 3.2.5 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2018-8039 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.
How O3 protects you
O3 Security's impact-aware SCA analyses which vulnerable code paths your application actually calls, so a match like CVE-2018-8039 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2018-8039. 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.
In OpenShift Logging the openshift-logging/elasticsearch6-rhel8 container bundles the vulnerable version of apache-cxf, but the vulnerable class is not shipped, hence this component is not affected by this vulnerability.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat Fuse 7.2 | cxf-core | RHSA-2018:3768 |
| Red Hat JBoss A-MQ 6.3 | cxf-core | RHSA-2018:3817 |
| Red Hat JBoss EAP 7.1 | see advisory | RHSA-2018:2277 |
| Red Hat JBoss EAP 7.1 | cxf-core | RHSA-2018:2425 |
| Red Hat JBoss Enterprise Application Platform 7.1 for RHEL 6 | eap7-apache-cxf-0:3.1.16-1.redhat_1.1.ep7.el6 | RHSA-2018:2276 |
| Red Hat JBoss Enterprise Application Platform 7.1 for RHEL 6 | eap7-activemq-artemis-0:1.5.5.013-1.redhat_1.1.ep7.el6 | RHSA-2018:2423 |
| Red Hat JBoss Enterprise Application Platform 7.1 for RHEL 7 | eap7-activemq-artemis-0:1.5.5.013-1.redhat_1.1.ep7.el7 | RHSA-2018:2424 |
| Red Hat Single Sign-On 7.2 | cxf-core | RHSA-2018:2279 |
Frequently Asked Questions
Is CVE-2018-8039 in your dependencies?
O3 Security finds CVE-2018-8039 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.