Self-Extracting Encrypted Files created by AttacheCase may insecurely load Dynamic Link Libraries


AttacheCase is an open source file encryption software provided by HiBARA Software. It can also create self-extracting encrypted files. Self-extracting encrypted files created by AttacheCase contain an issue with the DLL search path, which may lead to insecurely loading Dynamic Link Libraries (CWE-427).

Eili Masami of Tachibana Lab. reported this vulnerability to IPA.
JPCERT/CC coordinated with the developer under Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

CVSS V3 Severity:
Base Metrics 7.8 (High) [IPA Score]
  • Attack Vector: Local
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: Required
  • Scope: Unchanged
  • Confidentiality Impact: High
  • Integrity Impact: High
  • Availability Impact: High
CVSS V2 Severity:
Base Metrics 6.8 (Medium) [IPA Score]
  • Access Vector: Network
  • Access Complexity: Medium
  • Authentication: None
  • Confidentiality Impact: Partial
  • Integrity Impact: Partial
  • Availability Impact: Partial
Affected Products

HiBARA Software
  • AttacheCase ver. and earlier - CVE-2017-2271
  • AttacheCase ver. and earlier - CVE-2017-2272


Arbitrary code may be executed with the privilege of the user invoking a vulnerable self-extracting encrypted file.

[Update the Files]
Update AttacheCase and re-encrypt the affected files according to the information by the developer.
AttacheCase ver2.x are no longer supported. HiBARA Software recommends AttacheCase ver4.x as the successor to AttacheCase ver2.x to re-encrypt the affected files.

Keep following the practice explained in the following workarounds to securely treat self-extracted encrypted files.

[Apply Workarounds]
* When invoking a self-extracting encrypted file, make sure no unrelated files exist within the same directory. It is best to copy the installer into a newly created directory and invoke it from that directory
* Make sure no untrusted files exist within the directory where the self-extracting encrypted file is invoked.
* If you have some shared directory within your organization to place self-extracting encrypted files, make sure that this shared directory is read-only for non-administrative users
* Operate self-extracting encrypted files using a standard user (non-administrator) account. Administrator accounts should be used only when necessary.
Vendor Information

HiBARA Software
CWE (What is CWE?)

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

  1. CVE-2017-2271
  2. CVE-2017-2272

  1. JVN : JVN#61502349
  2. JVN : JVNTA#91240916
  3. National Vulnerability Database (NVD) : CVE-2017-2271
  4. National Vulnerability Database (NVD) : CVE-2017-2272
Revision History

  • [2017/07/14]
      Web page was published
      References : Contents were added
  • [2022/03/31]
      Solution was modified