CVE-2016-0763 — tomcat
MEDIUMCVE-2016-0763 is a medium-severity (CVSS 6.3) CWE-264 vulnerability in org.apache.tomcat:tomcat. EPSS puts its 30-day exploitation probability at 11.3% (96th percentile). A fix is available for org.apache.tomcat:tomcat — see the affected versions and patch details below.
Improper Verification of Source of a Communication Channel in Apache Tomcat
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-2016-0763 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 377,166 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.apache.tomcat:tomcat☕org.apache.tomcat:tomcat☕org.apache.tomcat:tomcatReal-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
The setGlobalContext method in org/apache/naming/factory/ResourceLinkFactory.java in Apache Tomcat 7.x before 7.0.68, 8.x before 8.0.31, and 9.x before 9.0.0.M3 does not consider whether ResourceLinkFactory.setGlobalContext callers are authorized, which allows remote authenticated users to bypass intended SecurityManager restrictions and read or write to arbitrary application data, or cause a denial of service (application disruption), via a web application that sets a crafted global context.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.tomcat:tomcat | ≥ 7.0.0&&< 7.0.68 | 7.0.68org.apache.tomcat:tomcat:7.0.68 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 8.0.0&&< 8.0.32 | 8.0.32org.apache.tomcat:tomcat:8.0.32 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 9.0.0M1&&< 9.0.0.M3 | 9.0.0.M3org.apache.tomcat:tomcat:9.0.0.M3 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.tomcat:tomcat, including transitive dependencies — a direct dependency you never call can still pull in a vulnerable version.
Fix
Update org.apache.tomcat:tomcat to 7.0.68 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-0763 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-2016-0763 can be triaged on real exposure rather than presence alone.
Tailored to CVE-2016-0763. 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 Enterprise Linux 7 | tomcat-0:7.0.69-10.el7 | RHSA-2016:2599 |
| Red Hat JBoss Enterprise Web Server 2 for RHEL 6 | tomcat7-0:7.0.54-23_patch_05.ep6.el6 | RHSA-2016:2807 |
| Red Hat JBoss Web Server 2.1 | tomcat7 | RHSA-2016:2808 |
| Red Hat JBoss Web Server 3.0 | see advisory | RHSA-2016:1089 |
| Red Hat JBoss Web Server 3 for RHEL 6 | httpd24-0:2.4.6-61.ep7.el6 | RHSA-2016:1087 |
| Red Hat JBoss Web Server 3 for RHEL 7 | httpd24-0:2.4.6-61.ep7.el7 | RHSA-2016:1088 |
Frequently Asked Questions
Is CVE-2016-0763 in your dependencies?
O3 Security finds CVE-2016-0763 across Maven dependencies, including transitive ones, and its impact-aware SCA ranks findings by whether your code actually calls the vulnerable path.