CVE-2026-48043
A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME.
Does this matter?
High impact if exploited, but EPSS currently rates exploitation as unlikely (0.62%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.
Description
Netty is a network application framework for development of protocol servers and clients. In netty-codec-http2 prior to versions 4.1.135.Final and 4.2.15.Final, the `DelegatingDecompressorFrameListener` class orchestrates HTTP/2 decompression by embedding a per-stream `EmbeddedChannel` that runs the appropriate decompression codec (gzip, deflate, zstd) and forwards decompressed chunks to a wrapped listener. Each decompressed chunk is a pooled `ByteBuf` handed to an anonymous `ChannelInboundHandlerAdapter` tail handler, which becomes the sole owner responsible for releasing it. A remote peer could send frames that would result in the flow-controller throwing and so trigger a resource leak which at the end might take down the whole JVM due OOME. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
- CVSS 3.1
- 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
- EPSS
- 0.62% probability · 48th percentile
- CISA KEV
- Not listed
- Weakness
- CWE-400, CWE-401, CWE-772
- Affected
- netty/netty
- Source
- security-advisories@github.com
References
- https://github.com/netty/netty/releases/tag/netty-4.1.135.FinalRelease Notes
- https://github.com/netty/netty/releases/tag/netty-4.2.15.FinalRelease Notes
- https://github.com/netty/netty/security/advisories/GHSA-c2gf-v879-257jVendor Advisory
- https://access.redhat.com/errata/RHSA-2026:26017
- https://access.redhat.com/errata/RHSA-2026:26018
- https://access.redhat.com/errata/RHSA-2026:26586
- https://access.redhat.com/errata/RHSA-2026:34608
- https://access.redhat.com/errata/RHSA-2026:36820
- https://access.redhat.com/errata/RHSA-2026:37390
- https://access.redhat.com/errata/RHSA-2026:41951
- https://access.redhat.com/errata/RHSA-2026:48124
- https://access.redhat.com/errata/RHSA-2026:48151
- https://access.redhat.com/errata/RHSA-2026:50085
- 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/errata/RHSA-2026:66488
- https://access.redhat.com/security/cve/CVE-2026-48043
- https://bugzilla.redhat.com/show_bug.cgi?id=2488442
- https://security.access.redhat.com/data/csaf/v2/vex/2026/cve-2026-48043.json
Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.