CVE-2016-8747 is a high-severity (CVSS 7.5) Information Exposure vulnerability in org.apache.tomcat:tomcat. A fix is available for org.apache.tomcat:tomcat — see the affected versions and patch details below.
Apache Tomcat allows remote attackers to read data that was intended to be associated with a different request
Exploitation Status
No confirmed exploitation observed yet
- CISA assesses this as automatable — exploitation doesn’t require manual, per-target effort, which raises the odds of mass scanning and opportunistic attacks.
- CISA’s own triage has not observed active exploitation or public proof-of-concept code for this CVE as of its last assessment.
Exploitation and automatability from CISA’s SSVC triage for CVE-2016-8747.
EPSS Exploitation Probability
Probability of exploitation in the next 30 days, from FIRST.org EPSS.
How urgent is this, really
Where this sits among everything scored
Real-World Exposure
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
An information disclosure issue was discovered in Apache Tomcat 8.5.7 to 8.5.9 and 9.0.0.M11 to 9.0.0.M15 in reverse-proxy configurations. Http11InputBuffer.java allows remote attackers to read data that was intended to be associated with a different request.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.tomcat:tomcat | ≥ 8.5.7&&< 8.5.10 | 8.5.10org.apache.tomcat:tomcat:8.5.10 |
| ☕Maven | org.apache.tomcat:tomcat | ≥ 9.0.0.M11&&< 9.0.0.M16 | 9.0.0.M16org.apache.tomcat:tomcat:9.0.0.M16 |
Affected Products
tomcatapacheoncommand insightnetapponcommand shiftnetappDetection & 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 8.5.10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-8747 is resolved across your whole dependency graph.
Workarounds
Assume what was exposed is already known: rotate any credential, token or key that the affected component could return, restrict the endpoint to callers that genuinely need it, and strip sensitive fields from responses and error output at the boundary rather than relying on the client not to read them.
Frequently Asked Questions
Is CVE-2016-8747 in your dependencies?
Find it across Maven, including transitive dependencies.