Uncontrolled Memory Allocation Affecting io.netty:netty-codec package, versions [4.1.0.Final, 4.1.46.Final)



    Attack Complexity Low
    Availability High

    Threat Intelligence

    EPSS 1.13% (85th percentile)
Expand this section
7.5 high
Expand this section
Red Hat
7.5 high

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  • Snyk ID SNYK-JAVA-IONETTY-564897
  • published 7 Apr 2020
  • disclosed 7 Apr 2020
  • credit Scott Mitchell

How to fix?

Upgrade io.netty:netty-codec to version 4.1.46.Final or higher.


io.netty:netty-codec is an event-driven asynchronous network application framework.

Affected versions of this package are vulnerable to Uncontrolled Memory Allocation while decoding a ZlibEncoded byte stream. An attacker could send a large ZlibEncoded byte stream to the Netty server, forcing the server to allocate all of its free memory to a single decoder.