Writeup of CVE-2017-13779

Remote Command Execution in GSTN Offline Utility Tool V1.1 ( CVE-2017-13779)

Description:

GSTN_offline_tool in India Goods and Services Tax Network (GSTN) Offline Utility tool before 1.2 executes winstart-server.vbs from the "C:\GST Offline Tool" directory, which has insecure permissions. This allows local users to gain privileges by replacing winstart-server.vbs with arbitrary VBScript code. For example, a local user could create VBScript code for a TCP reverse shell, and use that later for Remote Command Execution.

Official Fixes:

Fixed in Version 1.2

Latest Available Version: 1.2.1

Report Timeline

• 2017.8.29 Initial report to GSTN
• 2017.9.1 GSTN Security Team acks
• 2017.9.4 The bug is fixed in 1.2