# CVE-2023-34462: netty-handler SniHandler 16MB allocation

Source: https://junglewise.ai/threats/cve-2023-34462-netty-handler-snihandler-16mb-allocation  
Publisher: Junglewise Threat Intelligence, https://junglewise.ai/threats  
Published: 2023-06-20  
License: CC BY 4.0 with a link back

CVE-2023-34462 · Severity: low · CVSS 3.1 · Published 2023-06-20

netty-handler SniHandler 16MB allocation

Technologies: [io.netty:netty-handler (Maven)](https://junglewise.ai/threats/technologies/io-netty-netty-handler). Vendors: [Maven](https://junglewise.ai/threats/vendors/maven).

## Quick answers

**Is CVE-2023-34462 exploited in the wild?** No. Junglewise Threat Intelligence has no report of CVE-2023-34462 being exploited in the wild.

**How severe is CVE-2023-34462?** Low severity, with a CVSS score of 3.1, published 20 June 2023.

**Which products and versions are affected?** io.netty:netty-handler (Maven) ECOSYSTEM:introduced=0,fixed=4.1.94.Final.

**Is there a fix for CVE-2023-34462?** Yes. io.netty:netty-handler (Maven): upgrade to 4.1.94.Final or later. Junglewise finds every place you run it, drafts the upgrade and applies it once you approve.

**Am I affected by CVE-2023-34462?** Check whether you run io.netty:netty-handler (Maven) at an affected version. Junglewise does that check for you around the clock: connect your code, cloud and domains, and it matches new vulnerabilities like this one against what you actually run and tells you when one reaches you.

## How to fix

- io.netty:netty-handler (Maven): upgrade to 4.1.94.Final or later

  ```sh
  # set io.netty:netty-handler to 4.1.94.Final in your pom.xml or build.gradle
  ```


## Affected products

- io.netty:netty-handler (Maven) ECOSYSTEM:introduced=0,fixed=4.1.94.Final

## Identifiers

- CVE-2023-34462
- GHSA-6mjq-h674-j845

## Related threats

- [Netty is an asynchronous, event-driven network application framework. Prior to 4.1.137.Final and 4.2.17.Final, the default io.netty.handler.](https://junglewise.ai/threats/cve-2026-75596-netty-quadratic-pre-handshake-clienthello-reassembly-in-sni)
- [Netty SNI routing bypass via fragmented TLS ClientHello](https://junglewise.ai/threats/cve-2026-75595-netty-sni-routing-bypass-via-fragmented-tls-clienthello)
- [Netty disabled TLS hostname verification in netty-handler](https://junglewise.ai/threats/cve-2026-50010-netty-disabled-tls-hostname-verification-in-netty-handler)
- [Netty excessive memory allocation in SNIHandler](https://junglewise.ai/threats/cve-2026-45416-netty-excessive-memory-allocation-in-snihandler)
- [Netty IPv6 subnet filter bypass in netty-handler](https://junglewise.ai/threats/cve-2026-44249-netty-ipv6-subnet-filter-bypass-in-netty-handler)