Improper restriction of XML external entity references (XXE) in Proself


Proself provided by North Grid Corporation improperly restricts XML external entity references (XXE) (CWE-611).
The developer states that attacks exploiting this vulnerability have been observed.

North Grid Corporation reported this vulnerability to JPCERT/CC to notify users of its solution through JVN. JPCERT/CC and North Grid Corporation coordinated under the Information Security Early Warning Partnership.
CVSS Severity (What is CVSS?)

CVSS V3 Severity:
Base Metrics 7.5 (High) [IPA Score]
  • Attack Vector: Network
  • Attack Complexity: Low
  • Privileges Required: None
  • User Interaction: None
  • Scope: Unchanged
  • Confidentiality Impact: High
  • Integrity Impact: None
  • Availability Impact: None
CVSS V2 Severity:
Base Metrics 5.0 (Medium) [IPA Score]
  • Access Vector: Network
  • Access Complexity: Low
  • Authentication: None
  • Confidentiality Impact: Partial
  • Integrity Impact: None
  • Availability Impact: None
Affected Products

North Grid Corporation
  • Proself Enterprise Edition Ver5.62 and earlier
  • Proself Gateway Edition Ver1.65 and earlier
  • Proself Mail Sanitize Edition Ver1.08 and earlier
  • Proself Standard Edition Ver5.62 and earlier


By processing a specially crafted request containing malformed XML data, arbitrary files on the server, such as account information, may be read by an attacker.

[Update the software]
Update the software to the latest version according to the information provided by the developer.

[Apply the workaround]
Until the software is updated, the developer recommends to apply the workaround to mitigate the impact of this vulnerability.

[Stop using the products]
According to the developer, the following products are no longer supported. Stop using the vulnerable products and consider switching to alternatives.
  • Proself Enterprise/Standard Edition Ver.4 and earlier

Vendor Information

North Grid Corporation
CWE (What is CWE?)

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

  1. CVE-2023-45727

  1. JVN : JVN#95981460
  2. IPA SECURITY ALERTS : Security Alert for Vulnerability in Proself (JVN#95981460) (in Japanese)
  3. JPCERT REPORT : JPCERT-AT-2023-0022 (in Japanese)
Revision History

  • [2023/10/18]
      Web page was published