Vulnerability Description
Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, a remote unauthenticated peer can leak one direct `ByteBuf` per HTTP/2 `DATA` frame in applications that enable HTTP/2 content decompression via `DelegatingDecompressorFrameListener`. When a `DATA` frame is processed for a stream whose decompressor has already been closed, `Http2Decompressor.decompress(...)` calls `decompressor.writeInbound(data.retain())` and does not release the retained buffer on the error path, eventually exhausting direct memory and crashing the JVM. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.
CVSS Score
HIGH
Affected Products
| Vendor | Product | Versions |
|---|---|---|
| Netty | Netty | >= 4.1.0, < 4.1.136 |
Related Weaknesses (CWE)
References
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003bPatch
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6Patch
- https://github.com/netty/netty/releases/tag/netty-4.1.136.FinalRelease Notes
- https://github.com/netty/netty/releases/tag/netty-4.2.16.FinalRelease Notes
- https://github.com/netty/netty/security/advisories/GHSA-93wv-jw9v-4972ExploitVendor Advisory
- https://github.com/netty/netty/security/advisories/GHSA-93wv-jw9v-4972ExploitVendor Advisory
FAQ
What is CVE-2026-56819?
CVE-2026-56819 is a vulnerability with a CVSS score of 7.5 (HIGH). Netty is a network application framework for development of protocol servers and clients. In versions 4.2.0.Final through 4.2.15.Final and 4.1.0.Final through 4.1.135.Final, a remote unauthenticated p...
How severe is CVE-2026-56819?
CVE-2026-56819 has been rated HIGH with a CVSS base score of 7.5/10. Review the CVSS metrics above for detailed severity breakdown.
Is there a patch for CVE-2026-56819?
Check the references section above for vendor advisories and patch information. Affected products include: Netty Netty.