Netty: HTTP/2 decompression leaks ByteBuf reference count when the decompressor channel is already closed (Direct mem...

Date Jul 31, 2026
Type Vendor advisory
Signal High-risk advisory
Vendor / Product Maven ยท io.netty:netty-codec-http2
CVE CVE-2026-56819
High-risk advisory CVE-2026-56819

Summary

Netty: HTTP/2 decompression leaks ByteBuf reference count when the decompressor channel is already closed (Direct memory leak / OOM DoS)

Why it matters

GitHub has published a reviewed security advisory for io.netty:netty-codec-http2. Prioritize it with other application dependency updates, especially because EPSS places it in the 29% percentile.

Operator check

Check whether io.netty:netty-codec-http2 is present in application dependency manifests, lockfiles, or build images. Review the GitHub advisory and upgrade to a patched version where available. EPSS probability: 0.4%; percentile: 29%.

Sources

PatchBrief uses public sources. It does not scan environments, verify exposure, or replace vendor guidance.