CVE-2015-6321

highpriority · track · 32EPSS 0.028 · 86 %ileEUUS

grimoire priorityP2 · Scheduled

Exploitable?

—

no known exploitation

Likely / severe?

2.76% (86th) EPSS

CVSS 7.8 · high

Is it mine?

41 products

Check your exposure

Who says so?

3 sources

cnnvd · enisa_euvd · nvd

EPSS · scored 2026-10-27

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.

cvss

Technical severity, 0–10. One row per scoring source.

7.8

010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 6.6–7.8

v2.07.8highAV:N/AC:L/Au:N/C:N/I:N/A:Cprimary · NVD / NIST USexploitability 10 · impact 6.9

v2.06.6mediumAV:N/AC:L/Au:N/C:N/I:N/A:C/E:Usecondary · CVSS-BT (t0sche)

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-399USprimary

affected products (41)

Products and version ranges known to be affected.

n/a n/a≤ n/aenisa_euvdEU
cisco content security management appliance= 7.8.0-328nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 7.8.1-001nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 7.9.0-201nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 7.9.2-116nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.0.1-031nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.1.0-001nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.1.1-033nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.1.2-000nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.2.0-238nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.3.0-350nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.3.5-061nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.3.6-014nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.3.7-010nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 8.4.0-150nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 9.0.0-073nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco content security management appliance= 9.1.0-004nvdUScpe:2.3:a:cisco:content_security_management_appliance:*:*:*:*:*:*:*:*
cisco email security appliance= 7.6.1-000nvdUScpe:2.3:a:cisco:email_security_appliance:*:*:*:*:*:*:*:*
cisco email security appliance= 7.6.3-000nvdUScpe:2.3:a:cisco:email_security_appliance:*:*:*:*:*:*:*:*
cisco email security appliance= 7.7.0-000nvdUScpe:2.3:a:cisco:email_security_appliance:*:*:*:*:*:*:*:*

showing 20 of 41

also known as (3)

Other names and identifiers for this entity.

sources

Which sources assert this record, and when.

cnnvd enisa_euvd nvd NVD CVE.org MITRE

published 2015-11-06modified 2026-06-17

related (3,726)

Related entries.

ID	severity	EPSS	exploitable	published
CVE-2018-0180US	medium5.9OT critical	4.93% (92nd)	KEV	2018-03-28
Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected sy…
CVE-2018-0179US	medium5.9OT critical	4.93% (92nd)	KEV	2018-03-28
Multiple vulnerabilities in the Login Enhancements (Login Block) feature of Cisco IOS Software could allow an unauthenticated, remote attacker to trigger a reload of an affected sy…
CVE-2018-0161US	medium6.3OT critical	4.12% (91st)	KEV	2018-03-28
A vulnerability in the Simple Network Management Protocol (SNMP) subsystem of Cisco IOS Software running on certain models of Cisco Catalyst Switches could allow an authenticated,…
CVE-2018-0156US	high7.5OT critical	9.36% (95th)	KEV	2018-03-28
A vulnerability in the Smart Install feature of Cisco IOS Software and Cisco IOS XE Software could allow an unauthenticated, remote attacker to trigger a reload of an affected devi…
CVE-2018-0154US	high7.5OT critical	7.07% (94th)	KEV	2018-03-28
A vulnerability in the crypto engine of the Cisco Integrated Services Module for VPN (ISM-VPN) running Cisco IOS Software could allow an unauthenticated, remote attacker to cause a…

+3721 more

references (7)

External citations — patches, advisories, analysis.

scry

Attackers weaponise vulnerabilities like this against internet-exposed services. See what is exposed on your perimeter with a free passive scan.

Free scan