special character in query results in server errors
CVE: CVE-2020-27782
Component: undertow
CWE: CWE-400
Severity: Important
CVSS v3: 7.5/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Release date: 2020-01-01T00:00:00+00:00

A flaw was found in the Undertow AJP connector. Malicious requests and abrupt connection closes could be triggered by an attacker using query strings with non-RFC compliant characters resulting in a denial of service. The highest threat from this vulnerability is to system availability.


Remediation:
Before applying this update, ensure all previously released errata relevant to your system have been applied.

For details about how to apply this update, see:

https://access.redhat.com/articles/11258
Before applying this update, ensure all previously released errata relevant to your system have been applied. Also, back up your existing installation, including all applications, configuration files, databases and database settings. For details on how to apply this update, refer to: https://access.redhat.com/articles/11258
Before applying this update, ensure all previously released errata relevant to your system have been applied.

For details about how to apply this update, see:

https://access.redhat.com/articles/11258
Before applying this update, ensure all previously released errata relevant to your system have been applied.

For details about how to apply this update, see:

https://access.redhat.com/articles/11258
Before applying the update, back up your existing installation, including all applications, configuration files, databases and database settings, and so on.

Installation instructions are available from the Fuse 7.10.0 product
documentation page:
https://access.redhat.com/documentation/en-us/red_hat_fuse/7.10/
Before applying this update, make sure all previously released errata
relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258
Before applying this update, make sure all previously released errata relevant to your system have been applied.

For details on how to apply this update, refer to:

https://access.redhat.com/articles/11258
Before applying this update, back up your existing Red Hat JBoss Enterprise Application Platform installation and deployed applications.

The References section of this erratum contain a download link (you must log in to download the update).

The JBoss server process must be restarted for the update to take effect.
Before applying the update, back up your existing installation, including all applications, configuration files, databases and database settings, and so on.

The References section of this erratum contains a download link (you must log in to download the update).
Before applying the update, back up your existing installation, including all applications, configuration files, databases and database settings, and so on.

The References section of this erratum contains a download link for the update. You must be logged in to download the update.
Before applying the update, back up your existing installation, including all applications, configuration files, databases and database settings, and so on.

The References section of this erratum contains a download link for the update. You must be logged in to download the update.
The issue can be mitigated by using HTTP/1.1 instead of AJP to proxy to the back-end.