CVE-2021-31522
CRITICALCVE-2021-31522 is a critical-severity (CVSS 9.8) CWE-470 vulnerability in org.apache.kylin:kylin. O3 Security confirms whether CVE-2021-31522 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
Kylin can receive user input and load any class through Class.forName(...).
Real-World Exposure
org.apache.kylin:kylin☕org.apache.kylin:kylinReal-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
Kylin can receive user input and load any class through Class.forName(...). This issue affects Apache Kylin 2 version 2.6.6 and prior versions; Apache Kylin 3 version 3.1.2 and prior versions; Apache Kylin 4 version 4.0.0 and prior versions.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | org.apache.kylin:kylin | all versions | 3.1.3 |
| ☕Maven | org.apache.kylin:kylin | ≥ 4.0.0&&< 4.0.1 | 4.0.1 |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for org.apache.kylin:kylin. 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.kylin:kylin to 3.1.3 or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2021-31522 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-2021-31522 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-2021-31522. 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-2021-31522 in your dependencies?
O3 detects CVE-2021-31522 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.