CVE-2021-25833

Public Exploit

Description

A file extension handling issue was found in [server] module of ONLYOFFICE DocumentServer v4.2.0.71-v5.6.0.21. The file extension is controlled by an attacker through the request data and leads to arbitrary file overwriting. Using this vulnerability, a remote attacker can obtain remote code execution on DocumentServer.

Category

9.8
CVSS
Severity: Critical
CVSS 3.1 •
CVSS 2.0 •
EPSS 7.62% Top 10%
Vendor Advisory github.com
Affected: n/a n/a
Published at:
Updated at:

References

Link Tags
https://github.com/ONLYOFFICE/DocumentServer product vendor advisory
https://github.com/ONLYOFFICE/server product
https://github.com/ONLYOFFICE/server/blob/v5.6.0.21/DocService/sources/converterservice.js#L200 third party advisory
https://github.com/ONLYOFFICE/server/blob/v5.6.0.21/FileConverter/sources/converter.js#L593 third party advisory
https://github.com/ONLYOFFICE/server/blob/v5.6.0.21/FileConverter/sources/converter.js#L283 third party advisory
https://github.com/merrychap/poc_exploits/tree/master/ONLYOFFICE/CVE-2021-25833 third party advisory exploit

Frequently Asked Questions

What is the severity of CVE-2021-25833?
CVE-2021-25833 has been scored as a critical severity vulnerability.
How to fix CVE-2021-25833?
To fix CVE-2021-25833, make sure you are using an up-to-date version of the affected component(s) by checking the vendor release notes. As for now, there are no other specific guidelines available.
Is CVE-2021-25833 being actively exploited in the wild?
It is possible that CVE-2021-25833 is being exploited or will be exploited in a near future based on public information. According to its EPSS score, there is a ~8% probability that this vulnerability will be exploited by malicious actors in the next 30 days.
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