CVE-2021-25173

Vulnerability

The Open Design Alliance Drawings SDK versions prior to 2021.12 contain a memory allocation with excessive size vulnerability when parsing malformed DGN files. The issue results from improper validation of user-supplied data, which can lead to a write past the end of an allocated buffer [2]. Products that incorporate the SDK, such as Siemens JT2Go, are also affected.

Exploitation

An attacker can exploit this vulnerability by convincing a user to open a specially crafted DGN file. No authentication is required. The flaw is triggered during the parsing of the DGN file, where the lack of proper bounds checking allows an out-of-bounds write [2].

Impact

In the SDK itself, exploitation can cause a crash, exit, or restart, leading to denial of service. In affected products like Siemens JT2Go, the out-of-bounds write can be leveraged to achieve remote code execution in the context of the current process [2].

Mitigation

The vulnerability is fixed in Open Design Alliance Drawings SDK version 2021.12 [1]. Users of affected products should apply vendor updates. No workarounds are documented. The vulnerability is not listed in CISA's Known Exploited Vulnerabilities catalog.