CVE-2015-6321

Severity: high (CVSS 7.8 v2.0)
Exploited in the wild: not listed in CISA KEV
EPSS: 2.8% probability of exploitation in the next 30 days
Public exploit or detection template: none known
Published: 2015-11-06 · updated 2026-06-17
Weakness: CWE-399

Description

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 (SMA): 7.8.0-328, 7.8.1-001, 7.9.0-201, 7.9.2-116, 8.0.1-031, 8.1.0-001 (+10)
Cisco Email Security Appliance (ESA): 7.6.1-000, 7.6.3-000, 7.7.0-000, 7.7.1-000, 7.8.0-311, 8.5.6-052 (+8)
Cisco Web Security Appliance (WSA): 5.6.0-623, 6.0.0-000, 7.5.0-000, 7.5.0-825, 7.5.1-000, 7.5.2-000 (+4)

References

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