Reference page — cumulative record through Saturday, October 3, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-73508

CVE-2026-73508HIGH

Netty: Memory Leak in DNS Record Decoder via Malformed Domain Names

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  N  H    7.5   .0038   29.8     —

AFFECTED
  Product  Versions           Fixed
  netty    < 4.1.136.Final –  —

TIMELINE
  Aug 12  Reserved by GitHub_M
  Aug 13  Published (CNA: GitHub_M)
  Sep 23  RESCORED — CVE-2026-73508 (netty). CVSS 5.3 → 7.5 (NVD).

CWE-772 · CNA: GitHub_M · CVSS v3.1 · 5 references · NVD status: Analyzed

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.

Lifecycle

Complete event history — 3 events, chronological
Date	Event	Detail
August 12, 2026	Reserved	Reserved by GitHub_M
August 13, 2026	Published	Published (CNA: GitHub_M)
September 23, 2026	RESCORED	RESCORED — CVE-2026-73508 (netty). CVSS 5.3 → 7.5 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
netty	netty	—	< 4.1.136.Final	—

Weaknesses

CWE-772

References (5)

https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b [Patch]
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6 [Patch]
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final [Release Notes]
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final [Release Notes]
https://github.com/netty/netty/security/advisories/GHSA-mfg7-5gfp-c4w3 [Vendor Advisory]

Authoritative record: CVE-2026-73508 at cve.org

Vendors: netty

Weaknesses: CWE-772

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-73508 from the CVE Program record, NVD enrichment, the CISA KEV catalog, EPSS, and OSV advisories. The box score's numbers (CVSS, EPSS, KEV status) are current as of Saturday, October 3, 2026 UTC and are re-derived as the archive grows; only dated daily editions are immutable pages of record. The authoritative source for this identifier is cve.org.