DCOM RPC Worm out on the net
l33tdawg: Word to spasmgut for the link to the story.
A worm has started spreading early afternoon EDT (evening UTC Time) and is expected to continue spreading rapidly. This worms exploits the Microsoft Windows DCOM RPC Vulnerability announced July 16, 2003.
Names and Aliases: W32.Blaster.Worm (symantec),W32/Lovsan.worm (McAfee), WORM_MSBLAST.A (Trend Micro),Win32.Posa.Worm (CA),Lovsan (F-secure), MSBLASTER,Win32.Poza.
Infection sequence:
1. SOURCE sends packets to port 135 tcp with variation of dcom.c exploit to TARGET
2. this causes a remote shell on port 4444 at the TARGET
3. the SOURCE now sends the tftp get command to the TARGET, using the shell on port 4444,
4. the target will now connect to the tftp server at the SOURCE.
The name of the binary is msblast.exe. It is packed with UPX and will self extract. The size of the binary is about 11kByte unpacked, and 6kBytes packed:
MD5sum packed: 5ae700c1dffb00cef492844a4db6cd69 (6176 Bytes)
So far we have found the following properties:
- Scans sequentially for machines with open port 135, starting at a presumably random IP address
- uses multiple TFTP servers to pull the binary
- adds a registry key to start itself after reboot
