CVSS 3.1
7.5 highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:HCVE-2026-55831
High (7.5) in netty netty. EPSS 0.7% chance of exploitation in the next 30 days. Fixed in io.netty:netty-codec-http 4.1.136.Final, 4.2.16.Final.
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.
Severity
- EPSS
- 0.7% chance of exploitation in the next 30 days; higher than 51% of CVEs (scores of 2026-10-31)
- CWEs
- CWE-400, CWE-770
- Published
- Modified
- Record from
- the NVD, synced
Affected
- netty:netty
Packages (OSV)
| Advisory | Ecosystem | Package | Affected | Fixed in |
|---|---|---|---|---|
| GHSA-6jqx-86gh-f27w | Maven | io.netty:netty-codec-http | >=4.2.0.Final <4.2.16.Final | 4.2.16.Final |
| GHSA-6jqx-86gh-f27w | Maven | io.netty:netty-codec-http | >=4.1.0.Final <4.1.136.Final | 4.1.136.Final |
References
- https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b
- https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6
- https://github.com/netty/netty/releases/tag/netty-4.1.136.Final
- https://github.com/netty/netty/releases/tag/netty-4.2.16.Final
- https://github.com/netty/netty/security/advisories/GHSA-6jqx-86gh-f27w