CVE-2021-40439: Billion Laughs

Published Oct 7, 2021
·
Updated

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. All versions of Apache OpenOffice up to 4.1.10 are subject to this issue. expat in version 4.1.11 is patched.

Affected Software

1 affected component
Apache OpenOffice<=4.1.10

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade Apache OpenOffice to a version that resolves this vulnerability.

    Fixed in 4.1.11
  2. Upgrade

    Upgrade expat to a version that resolves this vulnerability.

    Fixed in 4.1.11

Event History

Oct 7, 2021
CVE Published
via MITRE·03:50 PM
Data Sourced
via MITRE·03:50 PM
DescriptionWeakness
Data Sourced
via NVD·04:15 PM
DescriptionSeverityWeaknessAffected Software
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Frequently Asked Questions

1

What is CVE-2021-40439?

CVE-2021-40439 is a vulnerability in Apache OpenOffice that allows for a denial of service attack and exploit through crafted XML files.

2

What is the severity of CVE-2021-40439?

The severity of CVE-2021-40439 is medium with a severity value of 6.5.

3

How does CVE-2021-40439 affect Apache OpenOffice?

CVE-2021-40439 affects Apache OpenOffice versions prior to 4.1.10 by allowing a denial of service attack and exploit via crafted XML files.

4

How can I mitigate CVE-2021-40439?

To mitigate CVE-2021-40439, it is recommended to update to Apache OpenOffice version 4.1.10 or later, which fixes the vulnerability.

5

Where can I find more information about CVE-2021-40439?

You can find more information about CVE-2021-40439 at the following references: [Reference 1](http://www.openwall.com/lists/oss-security/2021/10/07/4), [Reference 2](https://lists.apache.org/thread.html/r41eca5f4f09e74436cbb05dec450fc2bef37b5d3e966aa7cc5fada6d@%3Cannounce.apache.org%3E), [Reference 3](https://lists.apache.org/thread.html/rfb2c193360436e230b85547e85a41bea0916916f96c501f5b6fc4702%40%3Cusers.openoffice.apache.org%3E)

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