github.com
https://github.com/netty/netty CVE-2026-73508
MEDIUM
Netty: Memory Leak in DNS Record Decoder via Malformed Domain Names
Record summary
CVE-2026-73508 has a selected CVSS score of 5.3 (medium).
Description
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.
Description source: CVE List
Exploitation context
CISA SSVC decision
ExploitationNone
AutomatableYes
Technical impactPartial
CISA Coordinator · SSVC 2.0.3 · Evaluated Aug 13, 2026 · Source: CVE List
Affected products and versions
2| Product | Source | Version range | Status |
|---|---|---|---|
nettyBrowse netty / netty | CVE List | < 4.1.136.Final | affected |
| >= 4.2.0.Final, < 4.2.16.Final | affected | ||
io.netty:netty-codec-dnsBrowse Maven / io.netty:netty-codec-dns | GitHub Advisory | 4.2.0.Final to < 4.2.16.Final · Fixed in 4.2.16.Final | affected |
| Before 4.1.136.Final · Fixed in 4.1.136.Final | affected |
References
8github.com
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b github.com
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6 github.com
https://github.com/netty/netty/pull/17063 github.com
https://github.com/netty/netty/pull/17065 github.com
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final github.com
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final github.comConfirmation
https://github.com/netty/netty/security/advisories/GHSA-mfg7-5gfp-c4w3