Netty is an asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. The `SniHandler` can allocate up to 16MB of heap for each channel during the TLS handshake. When the handler or the channel does not have an idle timeout, it can be used to make a TCP server using the `SniHandler` to allocate 16MB of heap. The `SniHandler` class is a handler that waits for the TLS handshake to configure a `SslHandler` according to the indicated server name by the `ClientHello` record. For this matter it allocates a `ByteBuf` using the value defined in the `ClientHello` record. Normally the value of the packet should be smaller than the handshake packet but there are not checks done here and the way the code is written, it is possible to craft a packet that makes the `SslClientHelloHandler`. This vulnerability has been fixed in version 4.1.94.Final.
CVSS Details
- CVSS 3.1 Base Score: 6.5
- CVSS 3.1 Vector: (CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H)
Covered by Rapid7
| Product | Vendor Advisory | Solution File | Added | Published |
|---|---|---|---|---|
| Debian | — | Upgrade netty | Nov 27, 2023 | Jun 22, 2023 |
| Dell Powerstore Dsa2024225 | — | Upgrade Dell PowerStoreOS to the latest version | Oct 23, 2025 | May 29, 2024 |
| Red Hat Jboss Eap | — | Upgrade Red Hat JBoss EAP to the latest version | Sep 19, 2024 | Jun 23, 2023 |
| Redhat_linux | — | No solution exists | Jul 9, 2025 | Jun 22, 2023 |
| Suse | — | Upgrade netty-pomsUpgrade netty-tcnativeUpgrade netty-tcnative-javadocUpgrade nettyUpgrade netty-javadoc | Jul 27, 2023 | Jun 22, 2023 |
| Ubuntu | — | Upgrade libnetty-java | Sep 10, 2024 | Jun 22, 2023 |
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