The number of malware threats discovered doubles in September, according to a report issued today.

The report, compiled by Sophos, identifies over 4000 new security threats for September, double the number in the previous month. While the overall number of infected email has dropped to one in 300, the number of new threats continues to rise. The results indicate that cyber criminals are moving towards targeted attacks on small groups of users instead of mass emailed strikes.

"Internet criminals have had a busy September - producing twice as many new threats as they did in the previous month," said Graham Cluley, senior technology consultant for Sophos.

"The new malware we are detecting can be much more sinister than the old timers. It often aims to steal sensitive data and information - something which can be extremely damaging to both a company's reputation and its bottom line. We recommend that all organisations should put in place a consolidated security solution that protects against both known and unknown malware threats," he said.

Moreover the research reveals that Netsky-P continues to lead the list of malware for September and the top five threats retain their positions from the previous month.

The top ten malware in September were as follows:

1. Netsky-P
2. Mytob-AS
3. Bagle-Zip
4. Nyxem-D
5. Netsky-D
6. Mytob-E
7. Mytob-C
=8. Zafi-B
=8. MyDoom-O
10. MyDoom-AJ

The top ten hoaxes in September were as follows:

1. Olympic torch
2. Hotmail hoax
3. WTC Survivor
4. Bonsai kitten
5. MSN is closing down
6. Bill Gates fortune
7. Meninas da Playboy
8. Justice for Jamie
9. A virtual card for you
10.Budweiser frogs