CVE-2021-25631: denylist of executable filename extensions possible to bypass under windows

Published May 3, 2021
·
Updated

In the LibreOffice 7-1 series in versions prior to 7.1.2, and in the 7-0 series in versions prior to 7.0.5, the denylist can be circumvented by manipulating the link so it doesn't match the denylist but results in ShellExecute attempting to launch an executable type.

Affected Software

12 affected componentsFixes available
LibreOffice Libreoffice>=7.0.0<7.0.5
LibreOffice Libreoffice>=7.1.0<7.1.2
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0
alpine/libreoffice>=7.0.0<7.2.2.2-r0
7.2.2.2-r0

Remediation

Recommended actions to resolve this vulnerability, in priority order.

  1. Upgrade

    Upgrade alpine/libreoffice to a version that resolves this vulnerability.

    Fixed in 7.2.2.2-r0
  2. Upgrade

    Upgrade LibreOffice 7-1 series to a version that resolves this vulnerability.

    Fixed in 7.1.2
  3. Upgrade

    Upgrade LibreOffice 7-0 series to a version that resolves this vulnerability.

    Fixed in 7.0.5

Event History

May 3, 2021
CVE Published
via MITRE·11:10 AM
Data Sourced
via MITRE·11:10 AM
DescriptionWeakness
Data Sourced
via NVD·12:15 PM
DescriptionSeverityWeaknessAffected Software
Data Sourced
via OSV·12:15 PM
DescriptionSeverityAffected Software
Event
12:15 PM

Frequently Asked Questions

1

What is CVE-2021-25631?

CVE-2021-25631 is a vulnerability in the LibreOffice 7-1 series in versions prior to 7.1.2 and in the 7-0 series in versions prior to 7.0.5.

2

How severe is CVE-2021-25631?

CVE-2021-25631 has a severity rating of 8.8 (critical).

3

What is the description of CVE-2021-25631?

CVE-2021-25631 allows the circumvention of the denylist in LibreOffice, potentially enabling the execution of malicious code.

4

Which software versions are affected by CVE-2021-25631?

The LibreOffice 7-1 series in versions prior to 7.1.2 and the 7-0 series in versions prior to 7.0.5 are affected by CVE-2021-25631.

5

How can CVE-2021-25631 be exploited?

CVE-2021-25631 can be exploited by manipulating a link to bypass the denylist and execute arbitrary code using ShellExecute.

Company

Resources

Contact

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