high7.5
CVE-2026-42579
Netty is an asynchronous, event-driven network application framework.
Impact
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.
Affected packages
| Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|
| maven | io.netty:netty-codec-dns | >= 4.2.0.Alpha1, <= 4.2.12.Final | 4.2.13.Final |
Affected products
| Vendor | Product | Affected versions |
|---|---|---|
| Netty | Netty | before 4.1.133 from 4.2.0 before 4.2.13 |
Weakness classification
References
- NVD record
- CVE.org record
- GitHub advisory
- https://github.com/advisories/GHSA-cm33-6792-r9fm
- https://github.com/netty/netty/security/advisories/GHSA-cm33-6792-r9fm
- https://tools.ietf.org/html/rfc1035#section-2.3.4
- https://tools.ietf.org/html/rfc1035#section-4.1.4
- https://nvd.nist.gov/vuln/detail/CVE-2026-42579
- 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-2026:53645
- https://access.redhat.com/errata/RHSA-2026:53646
- 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://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-42579.json