Vulnerabilities
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CVE Vulnerabilities

CVE-2021-21409

Inconsistent Interpretation of HTTP Requests ('HTTP Request/Response Smuggling')

Published: Mar 30, 2021 | Modified: Nov 21, 2024
CVSS 3.x
5.9
MEDIUM
Source:
NVD
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
CVSS 2.x
4.3 MEDIUM
AV:N/AC:M/Au:N/C:N/I:P/A:N
RedHat/V2
RedHat/V3
5.9 MODERATE
CVSS:3.1/AV:N/AC:H/PR:N/UI:N/S:U/C:N/I:H/A:N
Ubuntu
MEDIUM
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Additional information
NVDhttps://nvd.nist.gov/vuln/detail/CVE-2021-21409
CWEhttps://cwe.mitre.org/data/definitions/444.html

Netty is an open-source, asynchronous event-driven network application framework for rapid development of maintainable high performance protocol servers & clients. In Netty (io.netty:netty-codec-http2) before version 4.1.61.Final there is a vulnerability that enables request smuggling. The content-length header is not correctly validated if the request only uses a single Http2HeaderFrame with the endStream set to to true. This could lead to request smuggling if the request is proxied to a remote peer and translated to HTTP/1.1. This is a followup of GHSA-wm47-8v5p-wjpj/CVE-2021-21295 which did miss to fix this one case. This was fixed as part of 4.1.61.Final.

Weakness

The product acts as an intermediary HTTP agent (such as a proxy or firewall) in the data flow between two entities such as a client and server, but it does not interpret malformed HTTP requests or responses in ways that are consistent with how the messages will be processed by those entities that are at the ultimate destination.

Affected Software

NameVendorStart VersionEnd Version
NettyNetty*4.1.61 (excluding)
AMQ Clients 2.y for RHEL 7RedHatqpid-proton-0:0.33.0-6.el7_9*
AMQ Clients 2.y for RHEL 8RedHatqpid-proton-0:0.33.0-8.el8*
EAP 7.3.8RedHatnetty*
OpenShift Logging 5.1RedHatopenshift-logging/elasticsearch6-rhel8:v6.8.1-67*
OpenShift Logging 5.2RedHatopenshift-logging/elasticsearch6-rhel8:v6.8.1-66*
OpenShift Logging 5.3RedHatopenshift-logging/elasticsearch6-rhel8:v6.8.1-65*
Red Hat AMQ 7.8.2RedHatnetty*
Red Hat AMQ 7.9.0RedHat*
Red Hat AMQ Streams 1.8.0RedHatnetty*
Red Hat build of Quarkus 2.2.3RedHatnetty*
Red Hat Data Grid 8.2.0RedHatnetty*
Red Hat EAP-XP 2.0.0 via EAP 7.3.x baseRedHatnetty*
Red Hat Fuse 7.10RedHatnetty*
Red Hat JBoss Enterprise Application Platform 7RedHatnetty*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-elytron-web-0:1.6.3-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-hal-console-0:3.2.15-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-hibernate-0:5.3.20-3.SP1_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-infinispan-0:9.4.23-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-ironjacamar-0:1.4.33-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-jberet-0:1.3.8-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-jboss-remoting-0:5.0.23-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-jboss-server-migration-0:1.7.2-7.Final_redhat_00008.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-netty-0:4.1.63-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-undertow-0:2.0.38-1.SP1_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-wildfly-0:7.3.8-1.GA_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-wildfly-elytron-0:1.10.13-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 6RedHateap7-wildfly-http-client-0:1.0.28-1.Final_redhat_00001.1.el6eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-elytron-web-0:1.6.3-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-hal-console-0:3.2.15-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-hibernate-0:5.3.20-3.SP1_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-infinispan-0:9.4.23-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-ironjacamar-0:1.4.33-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-jberet-0:1.3.8-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-jboss-remoting-0:5.0.23-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-jboss-server-migration-0:1.7.2-7.Final_redhat_00008.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-netty-0:4.1.63-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-undertow-0:2.0.38-1.SP1_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-wildfly-0:7.3.8-1.GA_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-wildfly-elytron-0:1.10.13-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 7RedHateap7-wildfly-http-client-0:1.0.28-1.Final_redhat_00001.1.el7eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-elytron-web-0:1.6.3-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-hal-console-0:3.2.15-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-hibernate-0:5.3.20-3.SP1_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-infinispan-0:9.4.23-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-ironjacamar-0:1.4.33-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-jberet-0:1.3.8-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-jboss-remoting-0:5.0.23-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-jboss-server-migration-0:1.7.2-7.Final_redhat_00008.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-netty-0:4.1.63-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-undertow-0:2.0.38-1.SP1_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-wildfly-0:7.3.8-1.GA_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-wildfly-elytron-0:1.10.13-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.3 for RHEL 8RedHateap7-wildfly-http-client-0:1.0.28-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.4 for RHEL 8RedHateap7-netty-0:4.1.63-1.Final_redhat_00001.1.el8eap*
Red Hat JBoss Enterprise Application Platform 7.4 on RHEL 7RedHateap7-netty-0:4.1.63-1.Final_redhat_00001.1.el7eap*
Red Hat Satellite 6.11 for RHEL 7RedHatcandlepin-0:4.1.13-1.el7sat*
Red Hat Satellite 6.11 for RHEL 8RedHatcandlepin-0:4.1.13-1.el8sat*
Red Hat Single Sign-On 7.4.8RedHatnetty*
Vert.x 4.1.0RedHatnetty*
NettyUbuntubionic*
NettyUbuntudevel*
NettyUbuntuesm-apps/bionic*
NettyUbuntuesm-apps/focal*
NettyUbuntuesm-apps/jammy*
NettyUbuntuesm-apps/noble*
NettyUbuntuesm-apps/xenial*
NettyUbuntufocal*
NettyUbuntugroovy*
NettyUbuntuhirsute*
NettyUbuntuimpish*
NettyUbuntujammy*
NettyUbuntukinetic*
NettyUbuntulunar*
NettyUbuntumantic*
NettyUbuntunoble*
NettyUbuntuoracular*
NettyUbuntuplucky*
NettyUbuntuquesting*
NettyUbuntutrusty*
NettyUbuntutrusty/esm*
NettyUbuntuupstream*
NettyUbuntuxenial*

Extended Description

HTTP requests or responses (“messages”) can be malformed or unexpected in ways that cause web servers or clients to interpret the messages in different ways than intermediary HTTP agents such as load balancers, reverse proxies, web caching proxies, application firewalls, etc. For example, an adversary may be able to add duplicate or different header fields that a client or server might interpret as one set of messages, whereas the intermediary might interpret the same sequence of bytes as a different set of messages. For example, discrepancies can arise in how to handle duplicate headers like two Transfer-encoding (TE) or two Content-length (CL), or the malicious HTTP message will have different headers for TE and CL. The inconsistent parsing and interpretation of messages can allow the adversary to “smuggle” a message to the client/server without the intermediary being aware of it. This weakness is usually the result of the usage of outdated or incompatible HTTP protocol versions in the HTTP agents.

Potential Mitigations

References

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