CVE-2026-47874: Pivotal Reactor Netty

Medium severity, CVSS 5.3. EPSS: 0.4% chance of exploitation in the next 30 days.

The vulnerability occurs when a client sends HTTP/1.1 pipelined requests over a single connection, causing the Reactor Netty HTTP server to consume an excessive amount of memory. Reactor Netty 1.3.0 - 1.3.6 Reactor Netty 1.1.0 - 1.2.18 Reactor Netty 1.0.52 and earlier

Affected products

• Pivotal Reactor Netty: before 1.0.53 (fixed in 1.0.53); from 1.1.0, before 1.2.19 (fixed in 1.2.19); from 1.3.0, before 1.3.6.1 (fixed in 1.3.6.1)

Published 2026-08-27. Last modified 2026-09-02.