Device Language Message Specification Director

An issue was discovered in Gurux GXDLMS Director through 8.5.1905.1301. When downloading OBIS codes, it does not verify that the downloaded files are actual OBIS codes and doesn't check for path traversal. This allows the attacker exploiting CVE-2020-8809 to send executable files and place them in an autorun directory, or to place DLLs inside the existing GXDLMS Director installation (run on next execution of GXDLMS Director). This can be used to achieve code execution even if the user doesn't have any add-ins installed.

Published: 2020-02-25T18:55:10.000Z
Updated: 2024-08-04T10:12:10.909Z

Gurux GXDLMS Director prior to 8.5.1905.1301 downloads updates to add-ins and OBIS code over an unencrypted HTTP connection. A man-in-the-middle attacker can prompt the user to download updates by modifying the contents of gurux.fi/obis/files.xml and gurux.fi/updates/updates.xml. Then, the attacker can modify the contents of downloaded files. In the case of add-ins (if the user is using those), this will lead to code execution. In case of OBIS codes (which the user is always using as they are needed to communicate with the energy meters), this can lead to code execution when combined with CVE-2020-8810.

Published: 2020-02-25T18:57:18.000Z
Updated: 2024-08-04T10:12:10.485Z