Review reviewHigh

CVE-2026-44891

netty

Netty is a network application framework for development of protocol servers and clients. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.stomp.StompSubframeDecoder fails to limit the total number of headers or their cumulative size per frame, and the maxLineLength parameter only restricts individual header lines. An attacker can send a large number of short headers that are accumulated in memory inside DefaultStompHeadersSubframe until the JVM throws an OutOfMemoryError, causing denial of service for servers exposing a STOMP endpoint based on StompSubframeDecoder. This issu...

CVSS: 7.5
EPSS: 0.42%
CISA KEV: Not listed
Published: 2026.07.18

PRIORITY ASSESSMENT

Review review

The CVSS severity warrants an early asset and exposure review.

Known exploitationNot established by KEV

Exploit probability0.42%

Technical severityCVSS 7.5

Vulnerability overview

Affected product and versions

Product: netty
Affected versions: >= < 4.1.136.Final, >= >= 4.2.0.Final, < 4.2.16.Final, < 4.1.136, >= 4.2.0 < 4.2.16
Fixed versions: 4.1.136, 4.2.16

Recommended response sequence

Confirm exposure before applying a vendor-supported change.

Full remediation guide

1
Identify
Confirm that netty and an affected version are present.
2
Prioritize
Combine exploitation signals with asset exposure and business criticality.
3
Remediate
Follow the vendor advisory or supported update path and preserve rollback options.
4
Verify
Recheck the version, service health, access paths, and relevant logs.

Technical data

CVSS vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CWE: CWE-400, CWE-770