High 7.5Published Jul 21, 2026

CVE-2026-55831Netty is a network application framework for development of protocol servers and clients.

Updated under an hour ago (2026-10-19 05:50 UTC)

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Every CVE for netty

Exploited in the last 30 days

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, Netty's SPDY SETTINGS decoder accepts a peer-declared SETTINGS entry count up to the 24-bit frame-length limit and materializes every unique setting ID in `DefaultSpdySettingsFrame`, allowing a remote SPDY/3.1 peer to send a syntactically valid roughly 2 MiB SETTINGS frame that creates 262144 map entries and amplifies network input into heap growth and ordered-map insertion work. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

CVSS: 7.5 HIGH (v3.1, NVD)CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Weakness (CWE): CWE-400, CWE-770
Known exploited: Not in CISA's KEV catalog
EPSS (exploitation in the next 30 days): Not loaded for this CVE
Assigned by: Not given
NVD analysis: Modified
Record last updated: Jul 23, 2026
First seen by InfoSec Signals: Oct 9, 2026

Affected products

Affected products

netty netty netty:netty	from 4.1.0 before 4.1.136; from 4.2.0 before 4.2.16	NVD

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-6jqx-86gh-f27wexploit, vendor-advisory

The CVE record on cve.org NVD's entry

The CVE record is authoritative. Products marked “from the name” were identified from the CNA's free-text names, not a CPE, and are matched less certainly. This product uses the NVD API but is not endorsed or certified by the NVD.