CVE-2015-6321: Cisco Content Security Management Appliance

High severity, CVSS 7.8. EPSS: 2.8% chance of exploitation in the next 30 days.

Cisco AsyncOS before 8.5.7-042, 9.x before 9.1.0-032, 9.1.x before 9.1.1-023, and 9.5.x and 9.6.x before 9.6.0-042 on Email Security Appliance (ESA) devices; before 9.1.0-032, 9.1.1 before 9.1.1-005, and 9.5.x before 9.5.0-025 on Content Security Management Appliance (SMA) devices; and before 7.7.0-725 and 8.x before 8.0.8-113 on Web Security Appliance (WSA) devices allows remote attackers to cause a denial of service (memory consumption) via a flood of TCP packets, aka Bug IDs CSCus79774, CSCus79777, and CSCzv95795.

Affected products

• Cisco Content Security Management Appliance: version 7.8.0-328 only; version 7.8.1-001 only; version 7.9.0-201 only; version 7.9.2-116 only; version 8.0.1-031 only; version 8.1.0-001 only; …
• Cisco Email Security Appliance: version 7.6.1-000 only; version 7.6.3-000 only; version 7.7.0-000 only; version 7.7.1-000 only; version 7.8.0-311 only; version 8.5.6-052 only; …
• Cisco Web Security Appliance: version 5.6.0-623 only; version 6.0.0-000 only; version 7.5.0-000 only; version 7.5.0-825 only; version 7.5.1-000 only; version 7.5.2-000 only; …

Published 2015-11-06. Last modified 2026-06-17.