---
id: CVE-2026-73508
title: 'Netty is an asynchronous, event-driven network application framework'
summary: >-
  Netty is an asynchronous, event-driven network application framework. Prior to
  4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.dns.AbstractDnsRecord,
  io.netty.handler.codec.dns.DefaultDnsRecordDecoder.decodeRecord(), and
  io.netty.…
severity: medium
cvss: 5.3
cvssVector: 'CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L'
cwe:
  - CWE-772
vendor: netty
product: netty
affected:
  - netty < 4.1.136
  - 'netty >= 4.2.0, < 4.2.16'
patched:
  - netty 4.2.16
published: '2026-08-13'
updated: '2026-09-23'
sourceUpdated: '2026-09-23T15:39:29.417'
source: NVD
sourceUrl: 'https://nvd.nist.gov/vuln/detail/CVE-2026-73508'
references:
  - url: >-
      https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b
    label: security-advisories@github.com
  - url: >-
      https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6
    label: security-advisories@github.com
  - url: 'https://github.com/netty/netty/releases/tag/netty-4.1.136.Final'
    label: security-advisories@github.com
  - url: 'https://github.com/netty/netty/releases/tag/netty-4.2.16.Final'
    label: security-advisories@github.com
  - url: 'https://github.com/netty/netty/security/advisories/GHSA-mfg7-5gfp-c4w3'
    label: security-advisories@github.com
  - url: >-
      https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73508.json
  - url: 'https://access.redhat.com/security/cve/CVE-2026-73508'
  - url: 'https://bugzilla.redhat.com/show_bug.cgi?id=2515377'
  - url: 'https://www.cve.org/CVERecord?id=CVE-2026-73508'
  - url: 'https://nvd.nist.gov/vuln/detail/CVE-2026-73508'
  - url: 'https://access.redhat.com/errata/RHSA-2026:68754'
  - url: 'https://access.redhat.com/errata/RHSA-2026:69296'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70230'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70228'
  - url: 'https://access.redhat.com/errata/RHSA-2026:70229'
tags:
  - nvd
  - csaf
  - vex
  - red-hat
  - score-dispute
epss: 0.00333
epssPercentile: 0.26732
scores:
  nvd: 5.3
  vendor: 7.5
ingestedAt: '2026-09-09T21:22:45.533Z'
---

## Overview

Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.dns.AbstractDnsRecord, io.netty.handler.codec.dns.DefaultDnsRecordDecoder.decodeRecord(), and io.netty.handler.codec.dns.DnsCodecUtil.decompressDomainName() failed to release retained or newly allocated ByteBuf objects when IDN.toASCII() or encodeDomainName() rejected a malformed domain name, allowing unauthenticated remote DNS packets to leak direct memory incrementally until denial of service. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

## Affected

- `netty < 4.1.136`
- `netty >= 4.2.0, < 4.2.16`

## Remediation

Upgrade past the affected range:

- `netty 4.2.16`

## Vendor advisories

- **RHSA-2026:68754** · Red Hat · fixed in: Red Hat OpenShift Dev Spaces 3.30 · released 2026-09-17 · [advisory](https://access.redhat.com/errata/RHSA-2026:68754)
- **Red Hat VEX** · Important · affected: Exploit Intelligence, OpenShift Serverless, Red Hat build of Apicurio Registry 3, Red Hat build of Debezium 3, Red Hat Build of Keycloak, Red Hat Data Grid 8, … · no fix planned: Red Hat JBoss Enterprise Application Platform 7, Exploit Intelligence, OpenShift Serverless, Red Hat build of Apicurio Registry 3, … · updated 2026-09-23 · [vex](https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-73508.json)
- **RHSA-2026:69296** · Red Hat · fixed in: Red Hat Data Grid 8.6.3 · released 2026-09-21 · [advisory](https://access.redhat.com/errata/RHSA-2026:69296)
- **RHSA-2026:70230** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 10 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70230)
- **RHSA-2026:70228** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 8 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70228)
- **RHSA-2026:70229** · Red Hat · fixed in: Red Hat JBoss EAP 8.1 for RHEL 9 · released 2026-09-22 · [advisory](https://access.redhat.com/errata/RHSA-2026:70229)