Cisco Firepower Threat Defense Software SSL Decryption Policy DoS (cisco-sa-ftd-ssl-decrypt-dos-DdyLuK6c)

high Nessus Plugin ID 149209
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The remote device is missing a vendor-supplied security patch


According to its self-reported version, Cisco FTD Software is affected by a denial of service (DoS) vulnerability in its SSL/TLS handler component due to insufficient validation of of SSL/TLS messages. An unauthenticated, remote attacker can exploit this issue to trigger a reload of an affected device causing a DoS condition.

Please see the included Cisco BIDs and Cisco Security Advisory for more information.

Note that Nessus has not tested for this issue but has instead relied only on the application's self-reported version number.


Upgrade to the relevant fixed version referenced in Cisco bug ID CSCvo46649

See Also

Plugin Details

Severity: High

ID: 149209

File Name: cisco-sa-ftd-ssl-decrypt-dos-DdyLuK6c-ftd.nasl

Version: 1.4

Type: local

Family: CISCO

Published: 4/30/2021

Updated: 5/3/2021

Dependencies: cisco_enumerate_firepower.nbin

Risk Information

CVSS Score Source: CVE-2021-1402


Risk Factor: Medium

Score: 4.4


Risk Factor: High

Base Score: 7.8

Temporal Score: 5.8

Vector: AV:N/AC:L/Au:N/C:N/I:N/A:C

Temporal Vector: E:U/RL:OF/RC:C


Risk Factor: High

Base Score: 8.6

Temporal Score: 7.5

Vector: CVSS:3.0/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:H

Temporal Vector: E:U/RL:O/RC:C

Vulnerability Information

CPE: cpe:/a:cisco:firepower_threat_defense

Required KB Items: installed_sw/Cisco Firepower Threat Defense

Exploit Ease: No known exploits are available

Patch Publication Date: 4/28/2021

Vulnerability Publication Date: 4/28/2021

Reference Information

CVE: CVE-2021-1402


CISCO-SA: cisco-sa-ftd-ssl-decrypt-dos-DdyLuK6c

IAVA: 2021-A-0205

CWE: 119