Yafuoku! contains an issue where it fails to verify SSL server certificates


Yafuoku! provided by Yahoo Japan Corporation contains an issue where it fails to verify SSL server certificates.

Zachary Mathis of Proactive Defense (Kobe Digital Labo) reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

Base Metrics: 2.6 (Low) [IPA Score]
  • Access Vector: Network
  • Access Complexity: High
  • Authentication: None
  • Confidentiality Impact: None
  • Integrity Impact: Partial
  • Availability Impact: None

Affected Products

Yahoo Japan Corporation
  • Yafuoku! ver.4.3.0 and earlier (for iOS, Android)


A man-in-the-minddle attack may allow an attacker to eavesdrop on an encrypted communication.

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

Yahoo Japan Corporation
CWE (What is CWE?)

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

  1. CVE-2013-4699

  1. JVN : JVN#68156832
  2. National Vulnerability Database (NVD) : CVE-2013-4699
Revision History

  Web page was published
  References : Content was added