Stonesoft - Company Announcement

STONESOFT CORPORATION: NEW NETWORK SECURITY THREAT CATEGORY PUTS THE FUNCTIONALITY OF ORGANIZATIONS' DATA CAPITAL AND SYSTEMS AT RISK

Stonesoft Corporation Stock Exchange Release 4 October 2010 at 9.30 AM

The R&D unit of Stonesoft Corporation has discovered a new and significant
security threat category, which enables intruding into organizations' data
systems. This puts the uninterrupted functionality of organizations' data
capital and systems at risk.

Most current security systems do not offer protection against these new kinds of
threats. Stonesoft's own research and test results as well as current expert
analysis prove that the threat is global and it affects all security products of
a certain type regardless of the vendor.

Stonesoft has reported to the national Finnish security authority CERT and
several other principal authorities."We have discovered a significant threat category, which we believe will change
the whole network security and require organizations extensive renewal of their
security systems. Most traditional network security solutions are too static to
cope with these unknown and constantly evolving threats. Stonesoft's software
based security solutions offer comprehensive protection also against these new
threats, which will improve our competitiveness on the market. We are beginning
to inform our customers and will disclose this significant discovery in large
scale in the near future", says Ilkka Hiidenheimo, CEO of Stonesoft.

Stonesoft estimates the discovery to open new business opportunities for the
company and to have a positive effect on the company's net sales and
profitability. However, at this point the company cannot estimate the magnitude
nor the schedule of this effect.



Stonesoft Corporation

Ilkka Hiidenheimo
CEO


For further information, please contact:

Ilkka Hiidenheimo, Chief Executive Officer, Stonesoft Corporation
Tel. +358 9 47 67 11
E-mail: ilkka.hiidenheimo@stonesoft.com


Distribution:
NASDAQ OMX Helsinki Ltd
Main media
www.stonesoft.com



[HUG#1448668]