Security readout for executives and security teams
Plain-English summary
ONLYOFFICE deployments using the default JWT signing key could let an unauthenticated attacker access the document editor websocket service as if trusted. The CVSS score is critical because successful abuse could affect confidentiality, integrity, and availability. The source bundle does not prove active exploitation.
Executive priority
Treat as urgent for any exposed ONLYOFFICE deployment. The issue is remotely reachable, requires no user interaction or privileges, and can undermine document platform trust if default JWT configuration is present.
Technical view
CVE-2021-43445 is an incorrect access control/authentication weakness tied to JWT protection on ONLYOFFICE document editor websockets. The CVE states all ONLYOFFICE versions as of 2021-11-08 were affected because a default JWT signing key could be used to authenticate.
Likely exposure
Highest concern is self-hosted or internet-reachable ONLYOFFICE document editor infrastructure present as of 2021-11-08, especially where websocket access is reachable and default JWT configuration remains in use. The bundle provides no precise CPE list.
Exploitation context
The CVE references public research on exploiting ONLYOFFICE websockets for unauthenticated remote code execution. However, KEV is false in the bundle, and no supplied source confirms active exploitation in the wild.
Researcher notes
Evidence is strong for the vulnerability class and severity, but incomplete for exact affected CPEs, vendor patch identifiers, and observed exploitation. Validate configuration first, then map findings to vendor-supported remediation.
Mitigation direction
- Check current ONLYOFFICE vendor guidance and release notes for supported fixes.
- Verify deployments are not using a default JWT signing key.
- Rotate any default JWT secret using supported configuration procedures.
- Restrict document editor websocket access to trusted networks where possible.
- Review logs for unusual document editor websocket authentication activity.
Validation and detection
- Inventory all ONLYOFFICE server and document editor deployments.
- Confirm installed versions and configuration date relative to 2021-11-08.
- Review JWT signing-key configuration for default or shared values.
- Confirm websocket endpoints are not unnecessarily internet-exposed.
- Check vendor documentation for patch or configuration status.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-287: Credential and account abuse lookup
Authentication and credential weaknesses can make valid-account abuse and credential telemetry useful review starting points. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-43445 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- Critical
- CVSS
- 9.8 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H3.95.9Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
9.8CriticalVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:H/I:H/A:H
Source materials
- CVE List V5 sourceCVE List V5
- https://github.com/ONLYOFFICE/serverCVE reference
- https://www.onlyoffice.com/CVE reference
- https://labs.nettitude.com/blog/exploiting-onlyoffice-web-sockets-for-unauthenticated-remote-code-execution/CVE reference
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Improper Authentication
Improper Authentication represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.