VulnerabilityModified

CVE-2026-42579

This creates a bidirectional attack surface: malicious DNS responses can exploit the decoder, and user-influenced hostnames can exploit the encoder.

CRITICAL 9.1EPSS 1.01%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (1.01%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

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.

CVSS 3.1: 9.1 CRITICALCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:H/A:H
EPSS: 1.01% probability · 61th percentile
CISA KEV: Not listed
Weakness: CWE-20, CWE-400, CWE-626, CWE-1286
Affected: netty/netty
Source: security-advisories@github.com

References

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.