A new vulnerability has been discovered which affects the Special Interest Group Network for Analysis and Liaison (SIGNAL) platform, specifically targeting versions 4.4. to 4.7.7. This vulnerability, identified as CVE-2023-38752, is classified as an 'improper authorization' issue, and it allows certain API users to access and view restricted attribute information marked as 'non-disclosure'. This post will detail the nature of the vulnerability, provide a code snippet illustrating the issue, and outline the available exploits and potential risks associated with the vulnerability.

Background on SIGNAL

SIGNAL is a widely-used, high-level communication platform that enables organizations and institutions to share data and collaborate efficiently. With an extensive number of API integrations, SIGNAL plays a crucial role in securing sensitive data and maintaining data privacy across various industries. Addressing vulnerabilities in software like SIGNAL is critical to ensuring the continued security of sensitive user information.

Vulnerability Details

Improper authorization vulnerability — CVE-2023-38752 — arises from authorized API users having the ability to access poster attribute information designated as 'non-disclosure' by the system settings. Unauthorized access to private or restricted information could present a variety of risks, such as data breaches, identity theft, and malicious attacks.

To better illustrate the vulnerability, consider the following code snippet

def api_get_poster_attribute(user, attribute_id):
  user_permissions = get_user_permissions(user)
  attribute_info = get_attribute_info(attribute_id)
  if attribute_info['non_disclosure']:
    if 'view_non_disclosure_attributes' not in user_permissions:
      return "Unauthorized Access"
  return attribute_info

In this Python code example, the function api_get_poster_attribute is designed to check the permissions of the API user before retrieving the attribute information. However, it fails to properly enforce the 'non-disclosure' setting, erroneously allowing users with certain permissions (e.g., 'view_non_disclosure_attributes') to access the restricted attribute information.

Exploit Details

Currently, there are no known public exploits available for this vulnerability. However, given the potential for unauthorized access to restricted attribute information, exploited systems may face significant data privacy risks, such as exposure of sensitive user information. It is, therefore, essential for organizations using affected versions of SIGNAL to address and secure their systems against this vulnerability.

Mitigation and Recommendations

To safeguard against this vulnerability, it is strongly recommended that users update their SIGNAL platform to the latest version, as subsequent versions have rectified the improper authorization issue. Additionally, ensure strict adherence to the principle of least privilege when assigning API user permissions to minimize the potential impact of unauthorized access to sensitive data.

For further information, please consult the following resources

SIGNAL's Official Advisory: [Link to official advisory once released]
CVE Information: https://cve.mitre.org/cgi-bin/cvename.cgi?name=CVE-2023-38752
National Vulnerability Database: https://nvd.nist.gov/vuln/detail/CVE-2023-38752


CVE-2023-38752 presents a significant risk to the privacy and security of user data within the SIGNAL platform, allowing unauthorized access to restricted attribute information. It is crucial that organizations using affected SIGNAL versions act swiftly to secure their systems and protect sensitive data. As always, a proactive approach to cybersecurity can help prevent many of the concerns associated with software vulnerabilities.


Published on: 08/09/2023 04:15:00 UTC
Last modified on: 08/18/2023 16:35:00 UTC