CVE-2016-5018
CRITICALCVE-2016-5018 is a critical-severity (CVSS 9.1) vulnerability in org.apache.tomcat:tomcat-jasper. 1 public exploit reference exists, so weaponization risk is real. O3 Security confirms whether CVE-2016-5018 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Authentication Bypass Using an Alternate Path or Channel in Apache Tomcat
Blast Radius
org.apache.tomcat:tomcat-jasper☕org.apache.tomcat:tomcat-jasper☕org.apache.tomcat:tomcat-jasper☕org.apache.tomcat:tomcat-jasper☕org.apache.tomcat:jasper☕org.apache.tomcat.embed:tomcat-embed-jasper☕org.apache.tomcat.embed:tomcat-embed-jasper☕org.apache.tomcat.embed:tomcat-embed-jasper+2 moreReal-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
In Apache Tomcat 9.0.0.M1 to 9.0.0.M9, 8.5.0 to 8.5.4, 8.0.0.RC1 to 8.0.36, 7.0.0 to 7.0.70 and 6.0.0 to 6.0.45 a malicious web application was able to bypass a configured SecurityManager via a Tomcat utility method that was accessible to web applications.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.tomcat:tomcat-jasper | ≥ 9.0.0.M1&&< 9.0.0.M10 | 9.0.0.M10 |
| ☕Maven | org.apache.tomcat:tomcat-jasper | ≥ 8.5.0&&< 8.5.5 | 8.5.5 |
| ☕Maven | org.apache.tomcat:tomcat-jasper | ≥ 8.0.0RC1&&< 8.0.37 | 8.0.37 |
| ☕Maven | org.apache.tomcat:tomcat-jasper | ≥ 7.0.0&&< 7.0.72 | 7.0.72 |
| ☕Maven | org.apache.tomcat:jasper | ≥ 6.0.0&&< 6.0.47 | 6.0.47 |
| ☕Maven | org.apache.tomcat.embed:tomcat-embed-jasper | ≥ 9.0.0.M1&&< 9.0.0.M10 | 9.0.0.M10 |
Research use only. For defensive security, authorized penetration testing, and academic research only. Never execute exploit code against systems without explicit written authorization.
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-jasper. O3's reachability analysis confirms whether the vulnerable code path is actually invoked in your application, so you act on real exposure instead of every transitive match.
Fix
Update org.apache.tomcat:tomcat-jasper to 9.0.0.M10 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2016-5018 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 pinpoints whether CVE-2016-5018 is reachable in your code and exactly where to fix it, then blocks exploitation in production at runtime until the patched version is deployed.
Tailored to CVE-2016-5018. Runtime protection reduces exposure until a permanent patch is applied and verified — it complements patching, it doesn't replace it.
Frequently Asked Questions
Is CVE-2016-5018 in your dependencies?
O3 detects CVE-2016-5018 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.