Language

The Free and Open Productivity Suite
Released: Apache OpenOffice 4.1.11

CVE-2021-40439

Apache OpenOffice Advisory

CVE-2021-40439 "Billion Laughs" fixed in Expat >=2.4.0

Fixed in Apache OpenOffice 4.1.11

Description

Apache OpenOffice has a dependency on expat software. Versions prior to 2.1.0 were subject to CVE-2013-0340 a "Billion Laughs" entity expansion denial of service attack and exploit via crafted XML files. ODF files consist of a set of XML files. expat 2.1.0 and earlier does not properly handle entities expansion unless an application developer uses the XML_SetEntityDeclHandler function, which allows remote attackers to cause a denial of service (resource consumption), send HTTP requests to intranet servers, or read arbitrary files via a crafted XML document, aka an XML External Entity (XXE) issue.
expat is a 3rd party library that is used in the Apache OpenOffice build process to make use of its functions.

Severity: Moderate

There are no known exploits of this vulnerability.
A proof-of-concept demonstration exists.

Thanks to the reporter for discovering this issue

Vendor: The Apache Software Foundation

Versions Affected

All Apache OpenOffice versions 4.1.10 and older are affected.
OpenOffice.org versions may also be affected.

Mitigation

Install Apache OpenOffice 4.1.11 for the latest maintenance and cumulative security fixes. Use the Apache OpenOffice download page.

Acknowledgments

The Apache OpenOffice Security Team thanks for pointing to this issue.

Further Information

For additional information and assistance, consult the Apache OpenOffice Community Forums or make requests to the users@openoffice.apache.org public mailing list.

The latest information on Apache OpenOffice security bulletins can be found at the Bulletin Archive page.


Security Home-> Bulletin-> CVE-2021-40439

Apache Software Foundation

Copyright & License | Privacy | Contact Us | Donate | Thanks

Apache, OpenOffice, OpenOffice.org and the seagull logo are registered trademarks of The Apache Software Foundation. The Apache feather logo is a trademark of The Apache Software Foundation. Other names appearing on the site may be trademarks of their respective owners.