Description
Netty is an asynchronous, event-driven network application framework. Prior to 4.2.13.Final, when decoding header blocks, the non-Huffman branch of io.netty.handler.codec.http3.QpackDecoder#decodeHuffmanEncodedLiteral may execute new byte[length] for a string literal before verifying that length bytes are actually present in the compressed field section. The wire encoding allows a very large length to be expressed in few bytes. There is no check that length <= in.readableBytes() before new byte[length]. This vulnerability is fixed in 4.2.13.Final.
Affected products
| Vendor | Product | Affected | Fixed |
|---|---|---|---|
| netty | netty | >= 4.2.0.Alpha1, < 4.2.13.Final | — |
| io.netty | netty-codec-http3 | >= 4.2.0.Alpha1, < 4.2.13.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 | — |
SUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES 15 SP7 | netty | 4.1.133-150200.4.46.1 | SUSE-SU-2026:2308-1 |
| SLES 15 SP7 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLES 15 SP6 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLES 15 SP5 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLES 15 SP4 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
Show 5 more (older releases, extended support, other products)Fewer releases
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| SLES for SAP 15 SP6 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLES for SAP 15 SP5 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLES for SAP 15 SP4 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLE HPC 15 SP5 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
| SLE HPC 15 SP4 | netty-tcnative | 2.0.77-150200.3.39.1 | SUSE-SU-2026:2308-1 |
openSUSE
Security tracker ↗| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| openSUSE Tumbleweed | netty | 4.1.133-1.1 | openSUSE-SU-2026:10795-1 |
Wolfi
| Release | Package | Fixed in | Advisory |
|---|---|---|---|
| Wolfi rolling | druid | 37.0.0-r8 | — |
| Wolfi rolling | opensearch-3 +2 | 3.6.0-r5 | — |
| Wolfi rolling | spark-4.1-scala-2.13 | 4.1.2-r1 | — |
| Wolfi rolling | trino-plugin-hive +7 | 481-r0 | — |
Affected packages
| Ecosystem | Package | Affected | Fixed | Record |
|---|---|---|---|---|
| Maven | io.netty:netty-codec-http3 | >= 4.2.0.Final, < 4.2.13.Final | 4.2.13.Final | GHSA-2c5c-chwr-9hqw |
Advisories 3
- WID-SEC-2026-1372 Netty: Mehrere Schwachstellen BSI CERT-Bund (WID) · Oct 15, 2026
- SUSE-SU-2026:2308-1 Security update for netty, netty-tcnative SUSE / openSUSE Security Updates · Jun 10, 2026
- openSUSE-SU-2026:10795-1 netty-4.1.133-1.1 on GA media SUSE / openSUSE Security Updates · May 17, 2026