CVE-2026-42579 — Security Box Score

CVE · referencelatest edition

Reference page — cumulative record through Wednesday, August 19, 2026 UTC. Reference pages update as the archive grows; only dated daily editions are immutable pages of record.

CVE-2026-42579CRITICAL

Netty: DNS Codec Input Validation Bypass in Netty (Encoder + Decoder)

  AV  AC  PR  UI  S  C  I  A   CVSS    EPSS   %ile   KEV
   N   L   N   N  U  N  H  H    9.1   .0101   60.3     —

AFFECTED
  Product  Versions                           Fixed
  netty    >= 4.2.0.Alpha1, < 4.2.13.Final –  —

TIMELINE
  Apr 28  Reserved by GitHub_M
  May 13  Published (CNA: GitHub_M)
  Aug 13  EXPLOIT PUBLISHED — CVE-2026-42579 (netty). Public exploit reference added.
  Aug 13  RESCORED — CVE-2026-42579 (netty). CVSS 7.5 → 9.1 (NVD).

CWE-20, CWE-400, CWE-626, CWE-1286 · CNA: GitHub_M · CVSS v3.1 · 13 references · NVD status: Modified

Description

Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final and 4.1.133.Final, Netty's DNS codec does not enforce RFC 1035 domain name constraints during either encoding or decoding. This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder. This vulnerability is fixed in 4.2.13.Final and 4.1.133.Final.

Lifecycle

Complete event history — 4 events, chronological
Date	Event	Detail
April 28, 2026	Reserved	Reserved by GitHub_M
May 13, 2026	Published	Published (CNA: GitHub_M)
August 13, 2026	EXPLOIT PUBLISHED	EXPLOIT PUBLISHED — CVE-2026-42579 (netty). Public exploit reference added.
August 13, 2026	RESCORED	RESCORED — CVE-2026-42579 (netty). CVSS 7.5 → 9.1 (NVD).

Affected

Affected products and packages — 1 row
Vendor	Product / Package	Ecosystem	Version introduced	Fixed
netty	netty	—	>= 4.2.0.Alpha1, < 4.2.13.Final	—

Weaknesses

CWE-20 · CWE-400 · CWE-626 · CWE-1286

References (13)

Authoritative record: CVE-2026-42579 at cve.org

Vendors: netty

Weaknesses: CWE-20 · CWE-400 · CWE-626 · CWE-1286

About this page

This is a reference page, not a dated page of record. It assembles the complete lifecycle of CVE-2026-42579 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 Wednesday, August 19, 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.