VulnerabilityAnalyzed

CVE-2026-44892

This insecure default configuration allows a malicious client or server to send an enormous number of headers, leading to a memory exhaustion Denial of Service via an `OutOfMemoryError`.

HIGH 7.5EPSS 0.28%

Does this matter?

High impact if exploited, but EPSS currently rates exploitation as unlikely (0.28%). Schedule it in the normal patch cycle and watch for a rise in EPSS or a public exploit.

Description

Netty is a network application framework for development of protocol servers and clients. Prior to version 4.2.15.Final, the default configuration of the `Http3ConnectionHandler` in the Netty HTTP/3 codec lacks an enforced maximum header size limit. When a peer does not explicitly specify `HTTP3_SETTINGS_MAX_FIELD_SECTION_SIZE`, the implementation defaults to an unbounded limit. This insecure default configuration allows a malicious client or server to send an enormous number of headers, leading to a memory exhaustion Denial of Service via an `OutOfMemoryError`. Version 4.2.15.Final contains a patch.

CVSS 3.1: 7.5 HIGHCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
EPSS: 0.28% probability · 20th percentile
CISA KEV: Not listed
Weakness: CWE-400, CWE-1188
Affected: netty/netty
Source: security-advisories@github.com

References

https://github.com/netty/netty/releases/tag/netty-4.2.15.FinalRelease Notes
https://github.com/netty/netty/security/advisories/GHSA-c2rx-5r8w-8xr2Vendor Advisory

Source: NVD record, EPSS from FIRST.org, KEV from CISA. Refreshed daily.