Description
Netty (io.netty:netty-codec-socks) versions 4.2.0.Final through 4.2.16.Final and 4.1.x through 4.1.136.Final contain null byte, CRLF, and credential injection vulnerabilities in the SOCKS4 (Socks4ClientEncoder) and SOCKS5 (Socks5ClientEncoder) client encoders, which fail to validate domain address and authentication (username/password) fields. An attacker able to control these fields can inject null bytes or CRLF characters to truncate or alter values, potentially enabling domain spoofing, SOCKS4 userid truncation, authentication data injection, and protocol confusion. Fixed in 4.2.17.Final and 4.1.137.Final.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| netty | netty | 4.2.0.Final – < 4.2.16.Final, < 4.1.137.Final | 4.2.16.Final |
Fixed in Linux distributions
Distributions backport fixes, so the version that fixes this vulnerability differs per release — upgrade to at least the version shown. From the distributions' security trackers and advisories.
Debian
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Debian 14 | netty | No fix yet | — |
| Debian 13 | netty | No fix yet | — |
| Debian 12 | netty | No fix yet | — |
Ubuntu
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu 26.10 | netty | No fix yet | — |
Show 7 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Ubuntu Pro 26.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 24.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 22.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 20.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 18.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 16.04 LTS | netty | No fix yet | — |
| Ubuntu Pro 14.04 LTS | netty | No fix yet | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | netty | 4.1.138-150200.4.56.1 | SUSE-SU-2026:4391-1 |
| SLES 15 SP7 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLES 15 SP6 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLES 15 SP5 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLES 15 SP4 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLES for SAP 15 SP5 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLES for SAP 15 SP4 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLE HPC 15 SP5 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
| SLE HPC 15 SP4 | netty-tcnative | 2.0.84-150200.3.51.1 | SUSE-SU-2026:4391-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | netty | 4.1.138-1.1 | openSUSE-SU-2026:11882-1 |
Advisories 3
- WID-SEC-2026-2712 Netty: Mehrere Schwachstellen BSI CERT-Bund (WID) · Nov 8, 2026
- SUSE-SU-2026:4391-1 Security update for netty, netty-tcnative SUSE / openSUSE Security Updates · Sep 30, 2026
- openSUSE-SU-2026:11882-1 netty-4.1.138-1.1 on GA media SUSE / openSUSE Security Updates · Sep 25, 2026
References
- GitHub Security Advisory (GHSA-cc6x-ffm5-83wf) vendor-advisory
- VulnCheck Advisory: Netty before 4.2.16.Final SOCKS Proxy Null Byte Injection third-party-advisory