Oct 19, 2026 · 12:13 UTC SEARCH
UNRATED KNOWN EXPLOITED
Vulnerability intelligence

CVE-2021-3199

VendorONLYOFFICE
ProductDocs
Known exploitedYes
Added to CISA KEVOctober 8, 2026
KEV due dateOctober 11, 2026
Known ransomware useNot identified by CISA

ONLYOFFICE Docs contains a path traversal vulnerability that can occur when JWT is used, via a /.. sequence in an image upload parameter and could allow for remote code execution.

Required action

Apply mitigations in accordance with vendor instructions, ensuring compliance with CISA’s BOD 26-04 Prioritizing Security Updates Based on Risk (see URL in Notes) guidance and CISA’s “Forensics Triage Requirements” (see URL in Notes). Follow applicable BOD 26-04 guidance for cloud services or discontinue use of the product if mitigations are unavailable. Stakeholders are responsible for evaluating each asset's internet exposure and ensuring adherence to BOD 26-04 patching guidelines.

CISA KEV status

This vulnerability is listed in CISA’s Known Exploited Vulnerabilities Catalog. Known ransomware campaign use: Unknown.

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