HP has been negotiating to buy ArcSight since it was put up for sale late last month, according to the Wall Street Journal.
The Journal says a deal could be announced as early as today (13 September), but the situation is still fluid and could fall apart.
HP has made several acquisitions this year, including security firm Fortify Software, Stratavia, 3Par and Palm as part of plans to expand into new areas.
HP's interest in ArcSight suggests that Intel's recent $6.8bn acquisition of security firm McAfee will herald a consolidation in the crowded security market, according to the Financial Times.
The paper said HP competitors Cisco Systems and IBM had already made acquisitions in security with a view to integrating them into services, because security is increasingly being considered a critical part of the decision-making process when ordering other goods or services.
This story was first published by Computer Weekly