Timestomp

Timestomping is a technique that modifies the timestamps of a file (the modify, access, create, and change times), often to mimic files that are in the same folder. This is done, for example, on files that have been modified or created by the adversary so that they do not appear conspicuous to forensic investigators or file analysis tools. Timestomping may be used along with file name Masquerading to hide malware and tools. [1]

ID: T1099

Tactic: Defense Evasion

Platform:  Linux, Windows

Permissions Required:  User, Administrator, SYSTEM

Data Sources:  File monitoring, Process monitoring, Process command-line parameters

Defense Bypassed:  Host forensic analysis

Version: 1.0

Examples

NameDescription
3PARA RAT

3PARA RAT has a command to set certain attributes such as creation/modification timestamps on files.[2]

APT28

APT28 has performed timestomping on victim files.[3]

APT32

APT32 has used scheduled task raw XML with a backdated timestamp of June 2, 2016. The group has also set the creation time of the files dropped by the second stage of the exploit to match the creation time of kernel32.dll. Additionally, APT32 has used a random value to modify the timestamp of the file storing the clientID.[4][5][6]

Bankshot

Bankshot modifies the time of a file as specified by the control server.[7]

China Chopper

China Chopper's server component can change the timestamp of files.[8][9][10]

Cobalt Strike

Cobalt Strike will timestomp any files or payloads placed on a target machine to help them blend in.[11]

Derusbi

The Derusbi malware supports timestomping.[12][13]

Elise

Elise performs timestomping of a CAB file it creates.[14]

Empire

Empire can timestomp any files or payloads placed on a target machine to help them blend in.[15]

FALLCHILL

FALLCHILL can modify file or directory timestamps.[16]

Gazer

For early Gazer versions, the compilation timestamp was faked.[17]

InvisiMole

InvisiMole samples were timestomped by the authors by setting the PE timestamps to all zero values. InvisiMole also has a built-in command to modify file times.[18]

Lazarus Group

Several Lazarus Group malware families use timestomping, including modifying the last write timestamp of a specified Registry key to a random date, as well as copying the timestamp for legitimate .exe files (such as calc.exe or mspaint.exe) to its dropped files.[19][20][21][22]

Misdat

Many Misdat samples were programmed using Borland Delphi, which will mangle the default PE compile timestamp of a file.[23]

OwaAuth

OwaAuth has a command to timestop a file or directory.[24]

POSHSPY

POSHSPY modifies timestamps of all downloaded executables to match a randomly selected file created prior to 2013.[25]

Psylo

Psylo has a command to conduct timestomping by setting a specified file’s timestamps to match those of a system file in the System32 directory.[26]

SEASHARPEE

SEASHARPEE can timestomp files on victims using a Web shell.[27]

TDTESS

After creating a new service for persistence, TDTESS sets the file creation time for the service to the creation time of the victim's legitimate svchost.exe file.[28]

TEMP.Veles

TEMP.Veles used timestomping to modify the $STANDARD_INFORMATION attribute on tools.[29]

USBStealer

USBStealer sets the timestamps of its dropper files to the last-access and last-write timestamps of a standard Windows library chosen on the system.[30]

Mitigation

Mitigation of timestomping specifically is likely difficult. Efforts should be focused on preventing potentially malicious software from running. Identify and block potentially malicious software that may contain functionality to perform timestomping by using whitelisting [31] tools like AppLocker [32] [33] or Software Restriction Policies [34] where appropriate. [35]

Detection

Forensic techniques exist to detect aspects of files that have had their timestamps modified. [1] It may be possible to detect timestomping using file modification monitoring that collects information on file handle opens and can compare timestamp values.

References

  1. Carvey, H. (2013, July 23). HowTo: Determine/Detect the use of Anti-Forensics Techniques. Retrieved June 3, 2016.
  2. Crowdstrike Global Intelligence Team. (2014, June 9). CrowdStrike Intelligence Report: Putter Panda. Retrieved January 22, 2016.
  3. Alperovitch, D.. (2016, June 15). Bears in the Midst: Intrusion into the Democratic National Committee. Retrieved August 3, 2016.
  4. Carr, N.. (2017, May 14). Cyber Espionage is Alive and Well: APT32 and the Threat to Global Corporations. Retrieved June 18, 2017.
  5. Dumont, R. (2019, March 20). Fake or Fake: Keeping up with OceanLotus decoys. Retrieved April 1, 2019.
  6. Dumont, R.. (2019, April 9). OceanLotus: macOS malware update. Retrieved April 15, 2019.
  7. Sherstobitoff, R. (2018, March 08). Hidden Cobra Targets Turkish Financial Sector With New Bankshot Implant. Retrieved May 18, 2018.
  8. FireEye. (2018, March 16). Suspected Chinese Cyber Espionage Group (TEMP.Periscope) Targeting U.S. Engineering and Maritime Industries. Retrieved April 11, 2018.
  9. Lee, T., Hanzlik, D., Ahl, I. (2013, August 7). Breaking Down the China Chopper Web Shell - Part I. Retrieved March 27, 2015.
  10. The Australian Cyber Security Centre (ACSC), the Canadian Centre for Cyber Security (CCCS), the New Zealand National Cyber Security Centre (NZ NCSC), CERT New Zealand, the UK National Cyber Security Centre (UK NCSC) and the US National Cybersecurity and Communications Integration Center (NCCIC). (2018, October 11). Joint report on publicly available hacking tools. Retrieved March 11, 2019.
  11. Strategic Cyber LLC. (2017, March 14). Cobalt Strike Manual. Retrieved May 24, 2017.
  12. Novetta. (n.d.). Operation SMN: Axiom Threat Actor Group Report. Retrieved November 12, 2014.
  13. Fidelis Cybersecurity. (2016, February 29). The Turbo Campaign, Featuring Derusbi for 64-bit Linux. Retrieved March 2, 2016.
  14. Falcone, R., et al.. (2015, June 16). Operation Lotus Blossom. Retrieved February 15, 2016.
  15. Schroeder, W., Warner, J., Nelson, M. (n.d.). Github PowerShellEmpire. Retrieved April 28, 2016.
  16. US-CERT. (2017, November 22). Alert (TA17-318A): HIDDEN COBRA – North Korean Remote Administration Tool: FALLCHILL. Retrieved December 7, 2017.
  17. ESET. (2017, August). Gazing at Gazer: Turla’s new second stage backdoor. Retrieved September 14, 2017.
  18. Hromcová, Z. (2018, June 07). InvisiMole: Surprisingly equipped spyware, undercover since 2013. Retrieved July 10, 2018.
  1. Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Unraveling the Long Thread of the Sony Attack. Retrieved February 25, 2016.
  2. Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Destructive Malware Report. Retrieved March 2, 2016.
  3. Novetta Threat Research Group. (2016, February 24). Operation Blockbuster: Loaders, Installers and Uninstallers Report. Retrieved March 2, 2016.
  4. Sherstobitoff, R., Malhotra, A. (2018, April 24). Analyzing Operation GhostSecret: Attack Seeks to Steal Data Worldwide. Retrieved May 16, 2018.
  5. Gross, J. (2016, February 23). Operation Dust Storm. Retrieved September 19, 2017.
  6. Dell SecureWorks Counter Threat Unit Threat Intelligence. (2015, August 5). Threat Group-3390 Targets Organizations for Cyberespionage. Retrieved August 18, 2018.
  7. Dunwoody, M.. (2017, April 3). Dissecting One of APT29’s Fileless WMI and PowerShell Backdoors (POSHSPY). Retrieved April 5, 2017.
  8. Falcone, R. and Miller-Osborn, J.. (2016, January 24). Scarlet Mimic: Years-Long Espionage Campaign Targets Minority Activists. Retrieved February 10, 2016.
  9. Davis, S. and Caban, D. (2017, December 19). APT34 - New Targeted Attack in the Middle East. Retrieved December 20, 2017.
  10. ClearSky Cyber Security and Trend Micro. (2017, July). Operation Wilted Tulip: Exposing a cyber espionage apparatus. Retrieved August 21, 2017.
  11. Miller, S, et al. (2019, April 10). TRITON Actor TTP Profile, Custom Attack Tools, Detections, and ATT&CK Mapping. Retrieved April 16, 2019.
  12. Calvet, J. (2014, November 11). Sednit Espionage Group Attacking Air-Gapped Networks. Retrieved January 4, 2017.
  13. Beechey, J. (2010, December). Application Whitelisting: Panacea or Propaganda?. Retrieved November 18, 2014.
  14. Tomonaga, S. (2016, January 26). Windows Commands Abused by Attackers. Retrieved February 2, 2016.
  15. NSA Information Assurance Directorate. (2014, August). Application Whitelisting Using Microsoft AppLocker. Retrieved March 31, 2016.
  16. Corio, C., & Sayana, D. P. (2008, June). Application Lockdown with Software Restriction Policies. Retrieved November 18, 2014.
  17. Microsoft. (2012, June 27). Using Software Restriction Policies and AppLocker Policies. Retrieved April 7, 2016.