CVE-2021-3199NVD

Vulnerability Summary

Directory traversal with remote code execution can occur in /upload in ONLYOFFICE Document Server before 5.6.3, when JWT is used, via a /.. sequence in an image upload parameter.

Severity Level

CRITICAL(9.8)

Published Date

Jan 26, 2021

Last Modified

Oct 8, 2026

Exploitation Status

ACTIVE

EPSS Score (30-Day)

8.22%Probability

Root Weakness (CWE)

CWE-22: Path Traversal ↗

The software uses external input to construct a pathname that is intended to identify a file or directory that is located underneath a restricted parent directory.

CVSS v3.1 Base Metrics — Score 9.8 (CRITICAL)

Attack VectorNetwork

Attack ComplexityLow

Privileges RequiredNone

User InteractionNone

ScopeUnchanged

ConfidentialityHigh

IntegrityHigh

AvailabilityHigh

Affected & Patched Versions

Affected Versions

Onlyoffice Document Server < 5.6.3

Patched Versions

Onlyoffice Document Server 5.6.3

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