OfficeApplication · Cybozu

CVE-2015-8484

MEDIUM · 5.4 CVSS v3.0 Published 2016-02-17
Mitigation only
No fix yet — a mitigation exists. There is no fixed release. A documented workaround reduces exposure in the meantime.
See remediation →
60/100
Remediation priority · Elevated
Remotely reachable Zero-click

Official description Straight from the sourceThe vendor's or NVD's own wording, published unedited. Authoritative, but often terse — it says what broke, rarely what to do.

NVD · unedited
Cybozu Office 9.9.0 through 10.3.0 allows remote authenticated users to bypass intended calendar-viewing restrictions via unspecified vectors, a different vulnerability than CVE-2015-8485, CVE-2015-8486, and CVE-2016-1152.

Technical summary Written by usOur analysis, written from the advisory, the CVSS vector and the affected-version data. It adds context the advisory leaves out, and never invents facts that are not in the source.

dbcve analysis · moderate confidence

Cybozu Office 9.9.0 through 10.3.0 contains an access control bypass vulnerability in its calendar functionality that allows authenticated users to view calendar entries they should not have permission to access. This is an authorization flaw rather than an authentication bypass.

MitigationUpgrade Cybozu Office to version 10.4.0 or later, which contains the fix for this calendar viewing restriction bypass. If immediate patching is not possible, review and restrict user calendar permissions as a compensating control.

Verify against the referenced sources before acting — the references below are authoritative for this CVE, this summary is not.

Affected products & versions What the vendor confirmedThe version ranges the vendor confirmed as vulnerable. If your version sits inside a range here, treat yourself as exposed until you have upgraded.

NVD · CPE data
OfficeApplication
Affected:= 9.9.0= 10.0.0= 10.0.1= 10.0.2= 10.1.0= 10.1.2= 10.2.0= 10.3.0

CVSS breakdown How the score is builtThe industry scoring standard. It rates how the flaw is reached, what it takes to exploit, and what an attacker gains — the score is derived from those, not the other way round.

From the vector
Attack vector
Network
Complexity
Low
Privileges
Low
User interaction
None
Scope
Unchanged
Confidentiality
Low
Integrity
None
Availability
Low

CVSS:3.0/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:N/A:L

Am I affected? How to checkSteps we derive from the advisory and the affected-version data, so you can decide whether this CVE reaches your setup. They are a guide, not a scan — your own configuration is the authority.

dbcve checks

Work through these to decide whether this CVE applies to you.

  1. Identify Cybozu Office version
    Access the system administration panel or check the product version information typically found in the About section of Cybozu Office. The version number is displayed in the system information or license details.
    Affected if The installed version is any of these: 9.9.0, 10.0.0, 10.0.1, 10.0.2, 10.1.0, 10.1.2, 10.0.2, or 10.3.0.
  2. Confirm calendar module is active
    Verify that the calendar application module is enabled for users in the Cybozu Office system. Check the application settings or user access controls to confirm calendar functionality is available.
    Affected if The calendar module is enabled and users have access to create or view calendar entries.
  3. Review calendar sharing permissions
    Examine the calendar sharing settings to determine if any entries are configured with permissions that restrict access to specific users or groups. Look for shared calendars where permission settings may not be properly enforced.
    Affected if Calendar entries exist with restricted permissions (such as private or group-limited entries) and users outside those permissions may still be able to view them.
  4. Test cross-user calendar access
    Create two test users with different calendar permission levels. Have User A create a private calendar entry, then attempt to access it from User B's account who should not have permission to view those entries.
    Affected if User B can view User A's private or restricted calendar entries despite not being granted permission.

You are affected if Cybozu Office version 9.9.0 through 10.3.0 is installed AND the calendar module is enabled, allowing unauthorized users to view restricted calendar entries.

Generated from the published advisory. Verify against your own configuration.

Check your environment

Paste your version and any relevant configuration and it will be compared against the affected criteria above. Do not include secrets or credentials.

AI-assisted, checked against the advisory. Informational, not a guarantee.

Remediation Closing itWhat it takes to close this. Where a vendor fix exists we point at it; where none exists we say so plainly, and can build one. Effort estimates are scoped from the advisory, not from your codebase.

From vendor data
Mitigation available No clean upgrade yet — mitigate in the meantime
Mitigation

Upgrade Cybozu Office to version 10.4.0 or later, which contains the fix for this calendar viewing restriction bypass. If immediate patching is not possible, review and restrict user calendar permissions as a compensating control.

Fix this in Office Scoped from the published advisory
  • Consultation2.0 h
  • Implementation4.0 h
  • Testing6.0 h
  • Review / QA3.0 h
15.0 hours of engineering $2,560
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Scan for this in your stack

Free · runs locally
dbcve dependency scanner

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References Go to the primary sourcePrimary sources — vendor advisories, patches and trackers. Where our summary and a reference disagree, the reference wins.

Primary sources

Practitioner notes

Contributed

Peer-ranked notes from engineers who’ve handled CVE-2015-8484 in production — separate from our analysis above.

No notes yet

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What this is

A place for practitioners to share what actually worked: a mitigation you’ve tested, a configuration change, a version- or environment-specific caveat, or a link to a verified patch. The most useful notes rise to the top as peers upvote them, so the signal stays high.

What belongs here
  • Verified mitigations, workarounds, and config changes
  • Version or environment caveats, and links to real fixes
  • No weaponised exploit code, or anything meant to cause harm
  • No spam, self-promotion, credentials, or personal data