Undertow: ajp request closes connection exceeding maxrequestsize

7.5 CVSS

Vulnerability Description

A flaw was found in Undertow. When an AJP request is sent that exceeds the max-header-size attribute in ajp-listener, JBoss EAP is marked in an error state by mod_cluster in httpd, causing JBoss EAP to close the TCP connection without returning an AJP response. This happens because mod_proxy_cluster marks the JBoss EAP instance as an error worker when the TCP connection is closed from the backend after sending the AJP request without receiving an AJP response, and stops forwarding. This issue could allow a malicious user could to repeatedly send requests that exceed the max-header-size, causing a Denial of Service (DoS).

Impact Analysis

Refer to official advisory for detailed impact metrics.

Remediation

Ensure systems are updated to the latest vendor-supplied patch levels.

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Credits & Attribution

No credits recorded in the NVD database.

References

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Affected Vendor

Red Hat

View all reports →

Affected Software

Red Hat JBoss Enterprise Application Platform 7.1 EUS for RHEL 7, Red Hat JBoss Enterprise Application Platform 7.3 EUS for RHEL 7, Red Hat build of Quarkus, Red Hat Data Grid 8, Red Hat Decision Manager 7, Red Hat Fuse 7, Red Hat JBoss Data Grid 7, Red Hat JBoss Enterprise Application Platform 7, Red Hat JBoss Fuse 6, Red Hat Process Automation 7, Red Hat Single Sign-On 7, Red Hat support for Spring Boot

Vulnerable Versions:

0:3.0.1-4.b08_redhat_00005.1.ep7.el7, 0:5.1.17-3.Final_redhat_00004.1.ep7.el7, 0:2.8.11.6-3.SP1_redhat_00003.1.ep7.el7, 0:4.0.12-1.Final_redhat_00002.1.ep7.el7, 0:4.1.63-2.Final_redhat_00003.1.ep7.el7, 0:1.4.18-16.SP14_redhat_00001.1.ep7.el7, 0:7.1.11-4.GA_redhat_00002.1.ep7.el7, 0:1.1.14-1.Final_redhat_00001.1.ep7.el7, 0:1.0.21-1.Final_redhat_00001.1.ep7.el7, 0:1.0.13-1.Final_redhat_00001.1.ep7.el7, 0:1.0.12-1.Final_redhat_00001.1.ep7.el7, 0:1.0.12-6.Final_redhat_00001.1.ep7.el7, 0:2.10.4-3.redhat_00006.1.el7eap, 0:2.10.4-5.redhat_00006.1.el7eap, 0:2.10.4-2.redhat_00006.1.el7eap, 0:1.7.2-16.Final_redhat_00017.1.el7eap, 0:4.1.63-5.Final_redhat_00003.1.el7eap, 0:2.0.41-4.SP5_redhat_00001.1.el7eap, 0:7.3.14-3.GA_redhat_00002.1.el7eap, 0:1.10.17-1.Final_redhat_00001.1.el7eap