Attached Link: http://securityresponse.symantec.com/avcenter/attack_sigs/sigs/MS-SQL_NullPacket_DoS.html

From Symantec's Website... MS-SQL_NullPacket_DoS Attack Category: Denial of Service Severity: High This attack could pose a serious security threat. You should take immediate action to stop any damage or prevent further damage from happening. Description This signature detects an attempt to exploit the NULL byte vulnerability in MS SQL Server. If Microsoft SQL Server 7.0 receives a TDS header with three or more NULL bytes as data, it will crash. The crash will generate an event in the log with ID 17055 "fatal exception EXCEPTION_ACCESS VIOLATION." Links SecurityFocus Website, BID: 817 Common Vulnerabilities and Exposures (CVE) Website, CVE-1999-0999 Microsoft Security Bulletin MS99-059