Skip to content

Data collected

CVEs Live

CVE-2021-3199: ONLYOFFICE Docs Server Path Traversal Vulnerability

ONLYOFFICE · Docs

Listed by CISA as exploited in the wild since 8 Oct 2026. Below: exploitation status, EPSS and every published CVSS, each with its source, then affected versions and references.

Build snapshot collected · KEV catalog 2026.10.21 · EPSS of 21 Oct 2026 · not a live feed: collected once, at build time

Description

as written by CISA (KEV catalog)

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

CISA KEV

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.

Affected products and versions

CVE record · mitre

  • n/a · n/a

    • affected: n/a

Status words (affected, unaffected, unknown) and version bounds are copied from the record. An upper bound such as “before 7.1.0” usually marks the first fixed version; confirm in the vendor advisory before planning an upgrade.

References

CISA KEV notes and CVE record

EPSS over the last 30 days

See also: the full KEV catalog

Related entries

Added in the same week (see the week)

Questions about CVE-2021-3199

Is CVE-2021-3199 being exploited?

Yes, according to CISA. CVE-2021-3199 was added to the Known Exploited Vulnerabilities catalog on 8 Oct 2026, which CISA does only with reliable evidence of exploitation in the wild. The catalog field for ransomware campaign use says "Unknown".

What is the deadline to remediate CVE-2021-3199?

CISA set 11 Oct 2026 as the due date for US Federal Civilian Executive Branch agencies. The date is binding only for those agencies; other organisations can read it as a measure of urgency.

What is the EPSS score of CVE-2021-3199?

20.1%, in the 97th percentile, in the FIRST EPSS model of 21 Oct 2026. It estimates the probability of exploitation activity in the following 30 days. For a CVE already in KEV the score is secondary: exploitation has been observed.

How severe is CVE-2021-3199?

CISA-ADP rates it 9.8 CRITICAL (CVSS 3.1). These are the published assessments as of 22 Oct 2026; this site does not rescore.

Which product does CVE-2021-3199 affect?

ONLYOFFICE Docs, as named in the CISA catalog. The affected versions listed in the CVE record are on this page; the vendor advisory in the references is the authority on fixed versions.

Related sections