Vulnerability · Published Aug 13, 2026 · Assigned by GitHub_M

CVE-2026-73507Netty: Denial of Service in XmlFrameDecoder via CPU Exhaustion

High 7.5

In plain English

A high-severity uncontrolled resource consumption in netty from netty. There are no confirmed reports of exploitation so far. The chance it is exploited in the next 30 days is estimated at 0.8% (higher than 57% of all known vulnerabilities). Fixed versions are available - upgrade the affected package.

Severity (CVSS 3.1)7.5High

Exploit odds (30 days)0.8%top 43.5% of all CVEs

Exploited in the wildNo reportsCISA SSVC: none

Attack toolingNoneno public tooling known

Official description

Netty is an asynchronous, event-driven network application framework. Prior to 4.1.136.Final and 4.2.16.Final, io.netty.handler.codec.xml.XmlFrameDecoder.decode() failed to preserve closing-tag parser state across invocations, so an unauthenticated remote attacker could trickle-feed repeated </ sequences that repeatedly rescanned the accumulated buffer and exhausted an EventLoop thread's CPU, causing denial of service with a maxFrameLength of 1 MB. This issue is fixed in versions 4.1.136.Final and 4.2.16.Final.

Affected packages & fixed versions

Ecosystem	Package	Fixed in	Advisory
Debian:12	netty	no fix listed	DEBIAN-CVE-2026-73507
Debian:13	netty	no fix listed	DEBIAN-CVE-2026-73507
Debian:14	netty	no fix listed	DEBIAN-CVE-2026-73507
Maven	io.netty:netty-codec-xml	4.2.16.Final	GHSA-v74w-7mr3-4qg3
Maven	io.netty:netty-codec-xml	4.1.136.Final	GHSA-v74w-7mr3-4qg3
Ubuntu:26.10	netty	no fix listed	UBUNTU-CVE-2026-73507

Affected products (as reported)

Vendor	Product	Versions
netty	netty	< 4.1.136.Final>= 4.2.0.Final, < 4.2.16.Final

Weakness: CWE-400 · Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H

References

https://github.com/netty/netty/security/advisories/GHSA-v74w-7mr3-4qg3 x_refsource_CONFIRM
https://github.com/netty/netty/commit/5b68c61f37aa4a3045cba624cbea239655c9003b x_refsource_MISC
https://github.com/netty/netty/commit/bb2ff68a1fb71cb4b0eb9a9e17b66c52aff680c6 x_refsource_MISC
https://github.com/netty/netty/releases/tag/netty-4.1.136.Final x_refsource_MISC
https://github.com/netty/netty/releases/tag/netty-4.2.16.Final x_refsource_MISC