CVE-2023-30328
CWE-287Published: May 4, 2023· Updated: Jun 17, 2026
Official Description
An issue in the helper tool of Mailbutler GmbH Shimo VPN Client for macOS v5.0.4 allows attackers to bypass authentication via PID re-use.
Risk Analysis
The Mailbutler Shimo VPN Client for macOS v5.0.4 contains an authentication bypass vulnerability due to PID re-use in its helper tool. This critical flaw allows attackers to gain unauthorized access, as reflected by its 9.8 CVSS score.
There is no known public exploit, and it is not in the KEV catalog. It is remotely exploitable with low attack complexity.
Update the Shimo VPN client to the latest available version provided by Mailbutler GmbH.
Technical Analysis
CVE-2023-30328 can be exploited remotely over the network without requiring physical or adjacent access, significantly expanding the attack surface for threat actors.
The vulnerability requires no privileges and no user interaction, making it a prime target for automated exploitation campaigns and worm-like propagation.
A successful exploit results in complete confidentiality breach (data exposure), full integrity compromise (data manipulation), availability disruption (denial of service), with a CVSS base score of 9.8.
From a weakness classification perspective (CWE-287): Authentication bypass vulnerabilities allow attackers to access protected resources without valid credentials.
CVSS v3.1 Vector Breakdown
Affected Vendors & Products
Exploit & PoC Resources
Official Patches & Advisories
All References (4)
Quick Facts
Related CVEs (CWE-287)
Recommended Actions
- →Apply vendor patches immediately
- →Monitor CVE-2023-30328 in threat intel feeds
- →Review IDS/IPS signatures for exploitation attempts