CVE-2017-6721: A vulnerability in the ingress processing of fragmented TCP packets by Cisco Wide Area Application Services...

Security readout for executives and security teams

CVE-2017-6721 is a denial-of-service issue in Cisco Wide Area Application Services. A remote unauthenticated attacker could cause the WAASNET process to restart by triggering vulnerable handling of fragmented TCP packets, disrupting acceleration services. The source bundle names affected and fixed WAAS releases but gives limited operational detail. Exposure is likely limited to organizations still running Cisco WAAS, especially release 6.3(1). Because the issue is remote and unauthenticated, reachable WAAS services on untrusted or poorly filtered paths carry higher operational risk. Prioritize remediation if Cisco WAAS remains in production or supports critical traffic paths. The issue affects availability rather than confidentiality, but remote unauthenticated DoS against WAN optimization can still disrupt business operations. Mitigation focus: Inventory Cisco WAAS deployments and identify release versions.; Upgrade affected systems to a Cisco-listed fixed release.; Review Cisco advisory guidance for any product-specific caveats..

Prepared

Jun 13, 2026, 04:25 UTC (UTC+00:00)

Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.