Table of contents exchange of letters with the minister executive summary


Followup action in respect of workstations used in unauthorised



Download 5.91 Mb.
View original pdf
Page110/329
Date27.11.2023
Size5.91 Mb.
#62728
1   ...   106   107   108   109   110   111   112   113   ...   329
Report of the COI into the Cyber Attack on SingHealth 10 Jan 2019
22.2 Followup action in respect of workstations used in unauthorised
logins to Citrix Server 1
372. Throughout and amidst the events on 13 June 2018, Benjamin and the
Citrix Team took steps to investigate Citrix Server 1 and the workstations involved in the unauthorised access to Citrix Server 1. They started first with trying to find the physical locations of the workstations by pinging them.
373. That morning, Benjamin also purchased three external hard disks to store forensic images of the workstations and Citrix Server 1. Pinging workstations VM 1 and VM 2 374. There was no response when Benjamin and the Citrix Team pinged workstations VM 1 and VM 2. In light of this, the Citrix Team suspected that these were virtual machines. Seizing the PHI 1 Workstation on 13 June 2018 375. When Benjamin was informed that the PHI 1 Workstation was one of the workstations from which unauthorised logins to Citrix Server 1 were made, he noted that it appeared to be the same workstation which he had re-imaged in January 2018. He suspected that the PHI 1 Workstation may have been



COI Report – Part IV
Page 128 of 425

compromised by malware again. He also suspected that the matter raised by the
Citrix Team on the morning of 13 June 2018 was a security incident.
376. There was a response from the PHI 1 Workstation when pinged, showing that it was in PHI 1. On 13 June 2018 itself, Benjamin contacted his IHiS colleagues who were based in PHI 1 and asked them to locate the PHI 1 Workstation, and to unplug the power cable. Thereafter, Benjamin acquired the forensic image of the PHI 1 Workstation on the same day. Arranging for the seizure of Workstation Con June 2018 377. Sometime in the afternoon of 13 June 2018, Benjamin had ascertained the user to whom Workstation C was assigned. Benjamin’s colleague contacted the user on the phone, and they learnt that he was overseas. The user consented to the workstation being seized for forensic investigations.
378. In an email conversation starting from the afternoon of 13 June 2018, Benjamin explained to the user’s head of department that Workstation C was found to be attempting to connect to the SCM database using several different username and password combinations over several days from 22 May to 4 June
2018, and requested for permission to seize the workstation. The head of department gave permission for the workstation to be seized, and further informed Benjamin that the user was overseas and had not used the workstation after 29 May 2018. Thereafter, arrangements were made for Workstation C to be seized on 18 June 2018, with a view to taking a forensic image.
379. This email correspondence was copied to an email group which included Ernest, who was still on holiday at the time. Shutting down Citrix Server 1 380. On Benjamin’s advice, the Citrix Team exported the server image of
Citrix Server 1 for the CERT to conduct further investigations, and shutdown
Citrix Server 1 thereafter.



Download 5.91 Mb.

Share with your friends:
1   ...   106   107   108   109   110   111   112   113   ...   329




The database is protected by copyright ©ininet.org 2024
send message

    Main page