CVE-2023-5379: Undertow: ajp request closes connection exceeding maxrequestsize

Published Oct 4, 2023
·
Updated

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 modcluster in httpd, causing JBoss EAP to close the TCP connection without returning an AJP response. This happens because modproxycluster 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).

Other sources

When an AJP request is sent that exceeds the max-header-size attribute in ajp-listener, JBoss EAP is marked as an error state by modcluster in httpd. The problem is that requests exceeding the max-header-size cause JBoss EAP to close the TCP connection without returning an AJP response.

A malicious user could exploit this behavior by repeatedly sending requests that exceed the max-header-size, it causes a denial-of-service attack. This is because modproxycluster marks JBoss 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.

Red Hat

Affected Software

4 affected components
redhat JBoss Enterprise Application Platform
redhat JBoss Enterprise Application Platform=7.0.0
redhat Single Sign-on=7.0
redhat undertow

Event History

Oct 4, 2023
Data Sourced
via Red Hat·11:53 AM
DescriptionSeverityAffected Software
Dec 12, 2023
CVE Published
via MITRE·09:54 PM
Data Sourced
via MITRE·09:54 PM
DescriptionSeverityWeakness
Data Sourced
via NVD·10:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is the severity of CVE-2023-5379?

CVE-2023-5379 has been rated as a moderate severity vulnerability.

2

How do I fix CVE-2023-5379?

To fix CVE-2023-5379, ensure that your JBoss EAP and Undertow installations are updated to the latest version that addresses this issue.

3

What systems are affected by CVE-2023-5379?

CVE-2023-5379 affects Red Hat JBoss Enterprise Application Platform, Red Hat Single Sign-On, and Red Hat Undertow.

4

What is the impact of CVE-2023-5379 on JBoss EAP?

CVE-2023-5379 can cause JBoss EAP to enter an error state and close TCP connections without responding to AJP requests.

5

When was CVE-2023-5379 reported?

CVE-2023-5379 was reported in 2023 and is associated with the Undertow server in JBoss EAP.

Contact

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