Snort » Snort : Security Vulnerabilities, CVEs, Published In 2007 (Denial of service)

The frag3 preprocessor in Snort 2.6.1.1, 2.6.1.2, and 2.7.0 beta, when configured for inline use on Linux without the ip_conntrack module loaded, allows remote attackers to cause a denial of service (segmentation fault and application crash) via certain UDP packets produced by send_morefrag_packet and send_overlap_packet.

Algorithmic complexity vulnerability in Snort before 2.6.1, during predicate evaluation in rule matching for certain rules, allows remote attackers to cause a denial of service (CPU consumption and detection outage) via crafted network traffic, aka a "backtracking attack."