Vulnerability Details CVE-2026-42579
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.
Exploit prediction scoring system (EPSS) score
EPSS Score 0.01
EPSS Ranking 61.4%
CVSS Severity
CVSS v3 Score 7.5
References
- https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm
- https://access.redhat.com/errata/RHSA-2026:23808
- https://access.redhat.com/errata/RHSA-2026:24502
- https://access.redhat.com/errata/RHSA-2026:25123
- https://access.redhat.com/errata/RHSA-2026:28010
- https://access.redhat.com/errata/RHSA-2026:36820
- https://access.redhat.com/errata/RHSA-2026:37390
- https://access.redhat.com/errata/RHSA-2026:49700
- https://access.redhat.com/errata/RHSA-2026:49701
- https://access.redhat.com/errata/RHSA-2026:53644
- https://access.redhat.com/errata/RHSA-2026:53806
- https://access.redhat.com/errata/RHSA-2026:54435
- https://access.redhat.com/errata/RHSA-2026:65126
- https://access.redhat.com/security/cve/CVE-2026-42579
- https://bugzilla.redhat.com/show_bug.cgi?id=2477217
- https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42579.json
Products affected by CVE-2026-42579
-
cpe:2.3:a:netty:netty:4.2.0
-
cpe:2.3:a:netty:netty:4.2.1
-
cpe:2.3:a:netty:netty:4.2.10
-
cpe:2.3:a:netty:netty:4.2.11
-
cpe:2.3:a:netty:netty:4.2.12
-
cpe:2.3:a:netty:netty:4.2.2
-
cpe:2.3:a:netty:netty:4.2.3
-
cpe:2.3:a:netty:netty:4.2.4
-
cpe:2.3:a:netty:netty:4.2.5
-
cpe:2.3:a:netty:netty:4.2.6
-
cpe:2.3:a:netty:netty:4.2.7
-
cpe:2.3:a:netty:netty:4.2.8
-
cpe:2.3:a:netty:netty:4.2.9