CVE-2016-3110 — mod_cluster-parent
HIGHCVE-2016-3110 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in org.jboss.mod_cluster:mod_cluster-parent. A fix is available for org.jboss.mod_cluster:mod_cluster-parent — see the affected versions and patch details below.
mod_cluster Denial of Service vulnerability
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-2016-3110 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 376,715 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.jboss.mod_cluster:mod_cluster-parentReal-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
mod_cluster, as used in Red Hat JBoss Web Server 2.1, allows remote attackers to cause a denial of service (Apache http server crash) via an MCMP message containing a series of = (equals) characters after a legitimate element.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.jboss.mod_cluster:mod_cluster-parent | all versions | 1.3.3.Finalorg.jboss.mod_cluster:mod_cluster-parent:1.3.3.Final |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.jboss.mod_cluster:mod_cluster-parent, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.jboss.mod_cluster:mod_cluster-parent to 1.3.3.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-3110 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-2016-3110 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2016-3110. 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.
| Product | Fixed in | Advisory |
|---|---|---|
| Red Hat JBoss Enterprise Application Platform 6.4 | mod_cluster | RHSA-2016:2056 |
| Red Hat JBoss Enterprise Application Platform 6.4 for RHEL 6 | hornetq-native-0:2.3.25-4.SP11_redhat_1.ep6.el6 | RHSA-2016:2055 |
| Red Hat JBoss Enterprise Application Platform 6.4 for RHEL 7 | hornetq-native-0:2.3.25-4.SP11_redhat_1.ep6.el7 | RHSA-2016:2054 |
| Red Hat JBoss Enterprise Web Server 2 for RHEL 6 | httpd-0:2.2.26-54.ep6.el6 | RHSA-2016:1649 |
| Red Hat JBoss Enterprise Web Server 2 for RHEL 7 | httpd22-0:2.2.26-56.ep6.el7 | RHSA-2016:1648 |
| Red Hat JBoss Web Server 2.1 | see advisory | RHSA-2016:1650 |
Frequently Asked Questions
Is CVE-2016-3110 in your dependencies?
O3 Security finds CVE-2016-3110 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.