TI-2021-07886 Aliases CVE-2021-25833 GHSA-f4rq-cvc9-g327

A file extension handling issue was found in [server] module of ONLYOFFICE DocumentServer…

HIGH 71CWE-22Published 2021-03-01 · Updated 2024-08-03

Key facts

Attack vector: Network
Privileges required: None
User interaction: None
Attack complexity: Low
Impact type: —
Confidentiality · integrity · availability: High · High · High
Fix status: No fix listed

Attack profile from CVSS 3.1 · NVD. Fix status from CNA.

Summary

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.

Why it matters now

EPSS 0.43534 98th percentileScored 2026-11-07

Public exploit Yes 1 exploit referenceTagged by NVD

Fix No fix listed No fixed version in the sources yet

SSVC decision points

Not available: CISA has not published SSVC decision points for this record.

Affected products

Vendor	Product	Affected versions	Fixed in	Status	Source
—	—	all versions	—	No fix listed	CNA

— Vendor— Affected all versions Fixed in — No fix listed CNA

CPE configurations NVD · 1

CPE	Versions	Role	Vendor
cpe:2.3:a:onlyoffice:document_server::::::::	4.2.0.71 – 5.6.0.21	Vulnerable	ONLYOFFICE

cpe:2.3:a:onlyoffice:document_server:*:*:*:*:*:*:*:* Versions 4.2.0.71 – 5.6.0.21 Vulnerable ·ONLYOFFICE

Remediation

No fixed version listed by the sources yet.

Timeline

2026-10-02 Threatist record created from CVE-2021-25833
2026-10-03 Alias added: GHSA-f4rq-cvc9-g327

References

Exploit 1

https://github.com/merrychap/poc_exploits/tree/master/ONLYOFFICE/CVE-2021-25833

Advisory 4

Other 1

https://github.com/ONLYOFFICE/server

TI-2021-02273 Path traversal in ONLYOFFICE Document Server enables code execution KEVCVSS 3.1CRITICAL 9.8
TI-2023-14162 An out of bounds memory access vulnerability in ONLYOFFICE DocumentServer 4.0.3 through… CVSS 3.1CRITICAL 9.8
TI-2023-14161 A use after free issue discovered in ONLYOFFICE DocumentServer 4.0.3 through 7.3.2 allows… CVSS 3.1CRITICAL 9.8
TI-2023-14163 Memory Exhaustion vulnerability in ONLYOFFICE Document Server 4.0.3 through 7.3.2 allows… CVSS 3.1HIGH 7.5
TI-2023-25368 Path Traversal vulnerability in ONLYOFFICE Document Server before v8.0.1 allows a remote… CVSS 3.1MEDIUM 6.7
TI-2023-27787 ONLYOFFICE Docs before 8.0.1 allows XSS because a macro is an immediately-invoked… CVSS 3.1MEDIUM 6.1

See all 20 →

Sources

This product uses the NVD API but is not endorsed or certified by the NVD. Sources and licences