CVE-2026-48043
netty-codec-http2: ByteBuf Reference-Count Leak in DelegatingDecompressorFrameListener Leads to Memory Exhaustion
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.
INFO
Published Date :
June 12, 2026, 4:16 p.m.
Last Modified :
June 30, 2026, 3:20 a.m.
Remotely Exploit :
Yes !
Source :
[email protected]
CVSS Scores
| Score | Version | Severity | Vector | Exploitability Score | Impact Score | Source |
|---|---|---|---|---|---|---|
| CVSS | 134c704f-9b21-4f2e-91b3-4a467353bcc0 | |||||
| CVSS 3.1 | MEDIUM | [email protected] | ||||
| CVSS 3.1 | HIGH | [email protected] | ||||
| CVSS 3.1 | HIGH | 0b0ca135-0b70-47e7-9f44-1890c2a1c46c |
Solution
- Update Netty to version 4.1.135.Final or later.
- Update Netty to version 4.2.15.Final or later.
Public PoC/Exploit Available at Github
CVE-2026-48043 has a 1 public
PoC/Exploit available at Github.
Go to the Public Exploits tab to see the list.
References to Advisories, Solutions, and Tools
Here, you will find a curated list of external links that provide in-depth
information, practical solutions, and valuable tools related to
CVE-2026-48043.
CWE - Common Weakness Enumeration
While CVE identifies
specific instances of vulnerabilities, CWE categorizes the common flaws or
weaknesses that can lead to vulnerabilities. CVE-2026-48043 is
associated with the following CWEs:
Common Attack Pattern Enumeration and Classification (CAPEC)
Common Attack Pattern Enumeration and Classification
(CAPEC)
stores attack patterns, which are descriptions of the common attributes and
approaches employed by adversaries to exploit the CVE-2026-48043
weaknesses.
We scan GitHub repositories to detect new proof-of-concept exploits. Following list is a collection of public exploits and proof-of-concepts, which have been published on GitHub (sorted by the most recently updated).
Kafka sink for Kusto
kafka-connector azure-data-explorer kusto
Java Shell Dockerfile
Results are limited to the first 15 repositories due to potential performance issues.
The following list is the news that have been mention
CVE-2026-48043 vulnerability anywhere in the article.
The following table lists the changes that have been made to the
CVE-2026-48043 vulnerability over time.
Vulnerability history details can be useful for understanding the evolution of a vulnerability, and for identifying the most recent changes that may impact the vulnerability's severity, exploitability, or other characteristics.
-
Initial Analysis by [email protected]
Jun. 15, 2026
Action Type Old Value New Value Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H Added CPE Configuration OR *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions up to (excluding) 4.1.135 *cpe:2.3:a:netty:netty:*:*:*:*:*:*:*:* versions from (including) 4.2.0 up to (excluding) 4.2.15 Added Reference Type GitHub, Inc.: https://github.com/netty/netty/releases/tag/netty-4.1.135.Final Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/netty/netty/releases/tag/netty-4.2.15.Final Types: Release Notes Added Reference Type GitHub, Inc.: https://github.com/netty/netty/security/advisories/GHSA-c2gf-v879-257j Types: Vendor Advisory -
New CVE Received by [email protected]
Jun. 12, 2026
Action Type Old Value New Value Added 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. Added CVSS V3.1 AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:L Added CWE CWE-400 Added CWE CWE-401 Added Reference https://github.com/netty/netty/releases/tag/netty-4.1.135.Final Added Reference https://github.com/netty/netty/releases/tag/netty-4.2.15.Final Added Reference https://github.com/netty/netty/security/advisories/GHSA-c2gf-v879-257j