Critical severity9.8NVD Advisory· Published Mar 1, 2021· Updated Jun 17, 2026
CVE-2021-25833
CVE-2021-25833
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.
AI Insight
LLM-synthesized narrative grounded in this CVE's description and references.
Affected products
3- cpe:2.3:a:onlyoffice:document_server:*:*:*:*:*:*:*:*Range: >=4.2.0.71,<=5.6.0.21
- ONLYOFFICE/DocumentServerdescription
- Range: v4.2.0.71-v5.6.0.21
Patches
Vulnerability mechanics
References
4- github.com/merrychap/poc_exploits/tree/master/ONLYOFFICE/CVE-2021-25833nvdExploitThird Party Advisory
- github.com/ONLYOFFICE/server/blob/v5.6.0.21/DocService/sources/converterservice.jsnvdThird Party Advisory
- github.com/ONLYOFFICE/server/blob/v5.6.0.21/FileConverter/sources/converter.jsnvdThird Party Advisory
- github.com/ONLYOFFICE/server/blob/v5.6.0.21/FileConverter/sources/converter.jsnvdThird Party Advisory
News mentions
0No linked articles in our index yet.