Cybozu KUNAI for Android information management vulnerability


Cybozu KUNAI for Android is a mobile client software for using Cybozu from an Android device. Cybozu KUNAI for Android provides a function to output log information when synchronizing data with Cybozu, however the function is disabled by default.

Cybozu KUNAI for Android contains an issue where it outputs log information when its data is synchronized with Cybozu for the first time, even if the log output function is disabled.

Kusano Kazuhiko reported this vulnerability to Cybozu, Inc., and Cybozu, Inc. reported this vulnerability to JPCERT/CC to notify users of its solution through JVN. JPCERT/CC and Cybozu, Inc. coordinated under the Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

CVSS V3 Severity:
Base Metrics 2.5 (Low) [IPA Score]
  • Attack Vector: Local
  • Attack Complexity: High
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Unchanged
  • Confidentiality Impact: Low
  • Integrity Impact: None
  • Availability Impact: None
CVSS V2 Severity:
Base Metrics 2.6 (Low) [IPA Score]
  • Access Vector: Network
  • Access Complexity: High
  • Authentication: None
  • Confidentiality Impact: Partial
  • Integrity Impact: None
  • Availability Impact: None
Affected Products

Cybozu, Inc.
  • Cybozu KUNAI for Android 3.0.4 to


If a user of Cybozu KUNAI for Android uses another malicious Android application, the log information managed by Cybozu KUNAI for Android may be disclosed.

[Update the Software]
Update to the latest version according to the information provided by the developer.
Vendor Information

Cybozu, Inc.
CWE (What is CWE?)

  1. No Mapping(CWE-Other) [IPA Evaluation]
CVE (What is CVE?)

  1. CVE-2017-2109

  1. JVN : JVN#88745657
  2. National Vulnerability Database (NVD) : CVE-2017-2109
Revision History

  • [2017/03/13]
      Web page was published
      References : Content was added