1. Symantec/
  2. Security Response/
  3. W32.HLLW.Deloder


Risk Level 2: Low

March 8, 2003
February 13, 2007 11:43:55 AM
Also Known As:
W32/Deloder-A [Sophos], WORM_DELODER.A [Trend], Win32.Deloder Worm [CA], W32/Deloder.worm [McAfee]
Systems Affected:

While Symantec Security Response is seeing an increase in submissions of W32.HLLW.Deloder, Symantec DeepSight Threat Management System has shown an overall decrease in activity on port 445. Security Response will continue to monitor this threat, and take action as appropriate.

W32.HLLW.Deloder is a network-aware worm that attempts to connect to a target host, using TCP port 445. This worm affects Windows 2000 and Windows XP only.

If the worm makes a successful connection, it copies the file, Inst.exe, to locations that are hard-coded in the worm. Inst.exe is a backdoor Trojan component that is detected as Backdoor.Dvldr. Then, W32.HLLW.Deloder will load from the Startup folder when you start Windows.

W32.HLLW.Deloder attempts to launch several remote services, which:
  • Copies and executes the backdoor Trojan
  • Copies and executes the worm
  • Deletes the default shares
  • Changes the attributes of the worm and backdoor Trojan to Read only

The worm exists as the Dvldr32.exe file and is packed with ASPack.

Antivirus Protection Dates

  • Initial Rapid Release version March 9, 2003
  • Latest Rapid Release version September 28, 2010 revision 054
  • Initial Daily Certified version March 9, 2003
  • Latest Daily Certified version September 28, 2010 revision 036
  • Initial Weekly Certified release date March 9, 2003
Click here for a more detailed description of Rapid Release and Daily Certified virus definitions.
Writeup By: Douglas Knowles

Search Threats

Search by name
Example: W32.Beagle.AG@mm
STAR Antimalware Protection Technologies
2016 Internet Security Threat Report, Volume 21
  • Twitter
  • Facebook
  • LinkedIn
  • Google+
  • YouTube