CVE-2021-25831: Critical severity onlyoffice vulnerability

Published Mar 1, 2021
·
Updated

A file extension handling issue was found in [core] module of ONLYOFFICE DocumentServer v4.0.0-9-v5.6.3. An attacker must request the conversion of the crafted file from PPTT into PPTX format. Using the chain of two other bugs related to improper string handling, a remote attacker can obtain remote code execution on DocumentServer.

Affected Software

1 affected component
Onlyoffice Document Server>=4.0.0-9<=5.6.3

Event History

Mar 1, 2021
CVE Published
via MITRE·03:08 PM
Data Sourced
via MITRE·03:08 PM
Description

Frequently Asked Questions

1

What is the severity of CVE-2021-25831?

CVE-2021-25831 is classified as a high severity vulnerability due to its potential for remote code execution.

2

How do I fix CVE-2021-25831?

To fix CVE-2021-25831, you should update ONLYOFFICE DocumentServer to version 5.6.4 or later.

3

What kind of attack does CVE-2021-25831 facilitate?

CVE-2021-25831 facilitates remote code execution by allowing an attacker to exploit file conversion processes.

4

Which versions of ONLYOFFICE DocumentServer are affected by CVE-2021-25831?

CVE-2021-25831 affects ONLYOFFICE DocumentServer versions from 4.0.0-9 up to 5.6.3.

5

What files are involved in the exploitation of CVE-2021-25831?

The exploitation of CVE-2021-25831 involves the conversion of crafted PPTT files into PPTX format.

Contact

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