CVE-2025-24970
HIGHCVE-2025-24970 is a high-severity (CVSS 7.5) Improper Input Validation vulnerability in io.netty:netty-handler. O3 Security confirms whether CVE-2025-24970 is actually reachable in your code before you act, and blocks exploitation at runtime until you patch.
SslHandler doesn't correctly validate packets which can lead to native crash when using native SSLEngine
Blast Radius
io.netty:netty-handlerReal-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
Netty, an asynchronous, event-driven network application framework, has a vulnerability starting in version 4.1.91.Final and prior to version 4.1.118.Final. When a special crafted packet is received via SslHandler it doesn't correctly handle validation of such a packet in all cases which can lead to a native crash. Version 4.1.118.Final contains a patch. As workaround its possible to either disable the usage of the native SSLEngine or change the code manually.
Affected Packages
| Ecosystem | Package | Vulnerable range | Fix |
|---|---|---|---|
| ☕Maven | io.netty:netty-handler | ≥ 4.1.91.Final&&< 4.1.118.Final | 4.1.118.Final |
Detection & mitigation playbook
Open-source dependencyDetect
Scan your dependency tree (package-lock.json, pnpm-lock.yaml, requirements.txt, go.sum, etc.) for io.netty:netty-handler. 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 io.netty:netty-handler to 4.1.118.Final or later, then make sure no transitive (indirect) dependency still pins the vulnerable range — O3 confirms CVE-2025-24970 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-2025-24970 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-2025-24970. 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-2025-24970 in your dependencies?
O3 detects CVE-2025-24970 across Maven dependencies and uses function-level reachability to confirm whether the vulnerable code path is actually reachable — not just present. No false positives.