CVE-2026-50560
Description
Netty is a network application framework for development of protocol servers and clients. Prior to versions 4.1.135.Final and 4.2.15.Final, Netty HTTP/2 max header size handling produces an attack similar to HTTP/2 Rapid Reset. There is a setting in the http2 specification called `SETTINGS_MAX_HEADER_LIST_SIZE`. When a client sends that setting to Netty, it appears that Netty will behave as follows: read the request; proxy the request to the origin; attempt to produce a response; and create an exception while writing the headers for the response. Functionally, this should be similar to the http2 reset attack, but with a different on-the-wire signature. Versions 4.1.135.Final and 4.2.15.Final patch the issue.
How to fix CVE-2026-50560
No fixed version has been published yet. Mitigate by removing the affected package or applying upstream guidance from the references below.
- —no fix listed
Is CVE-2026-50560 being exploited?
No exploitation signal available. Neither CISA KEV nor a current EPSS score has been published for CVE-2026-50560.
Affected packages (1)
- from 0
CVSS scores
| Source | Version | Severity | Vector |
|---|---|---|---|
| nvd | CVSS 4.0 | MEDIUM6.9 | CVSS:4.0/AV:N/AC:L/AT:N/PR:N/UI:N/VC:N/VI:N/VA:L/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X |