Security readout for executives and security teams
Plain-English summary
CVE-2021-20756 lets a logged-in user view Cybozu Garoon Address data they should not be allowed to see. The issue affects Cybozu Garoon versions 4.0.0 through 5.0.2. The public record does not provide CVSS scoring or evidence of active exploitation.
Executive priority
Treat this as a confidentiality issue for internal contact or address-book data. Prioritize remediation if Garoon Address contains sensitive employee, customer, or partner information, especially in environments with broad authenticated user populations.
Technical view
This is a viewing-restriction bypass in the Address component of Cybozu Garoon. A remote authenticated attacker can obtain Address data without the required viewing privilege. Public source details are sparse: no CWE, CVSS vector, exploit method, or confirmed remediation details are included in the provided bundle.
Likely exposure
Exposure is limited to organizations running Cybozu Garoon 4.0.0 through 5.0.2 with authenticated users who should have restricted Address visibility.
Exploitation context
The vulnerability requires remote authentication. The provided sources do not show CISA KEV listing, active exploitation, public exploit availability, or unauthenticated attack capability.
Researcher notes
The public bundle establishes affected product, affected versions, attacker authentication requirement, and data exposure outcome. It does not include exploit details, root-cause mechanics, CVSS, CWE, or a named patch level, so validation should stay focused on version exposure and vendor guidance.
Mitigation direction
- Inventory Cybozu Garoon deployments and identify versions 4.0.0 through 5.0.2.
- Check Cybozu and JVN advisories for vendor-supported updates or workarounds.
- Review Garoon Address visibility settings and remove unnecessary user access.
- Audit recent Address data access by users without expected viewing privileges.
Validation and detection
- Confirm installed Cybozu Garoon version against the affected range.
- Verify whether Address viewing restrictions are configured for sensitive contact data.
- Review logs for unexpected Address access by authenticated low-privilege users.
- Confirm remediation status against Cybozu or JVN vendor guidance.
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.
CVE-2021-20756 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
- Unknown
- CVSS
- Not scored
- Known Exploited
- No
- Published
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 and timeline data
No CVSS vectors or timeline events were available in the normalized CVE source material.
Source materials
- CVE List V5 sourceCVE List V5
- https://cs.cybozu.co.jp/2021/007206.htmlCVE reference · x_refsource_MISC
- https://jvn.jp/en/jp/JVN54794245/index.htmlCVE reference · x_refsource_MISC
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.