CVE-2020-3533

mediumpriority · track · 31EPSS 0.018 · 78 %ileEURUUS
grimoire priorityP3 · Track
Exploitable?
—
no known exploitation
Likely / severe?
1.78% (78th) EPSS
CVSS 5 · medium
Is it mine?
20 products
Check your exposure
Who says so?
5 sources
cnnvd · enisa_euvd · fstec_bdu · cisco_csaf

EPSS · scored 2026-10-27

A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly. The vulnerability is due to a lack of sufficient memory management protections under heavy SNMP polling loads. An attacker could exploit this vulnerability by sending a high rate of SNMP requests to the SNMP daemon through the management interface on an affected device. A successful exploit could allow the attacker to cause the SNMP daemon process to consume a large amount of system memory over time, which could then lead to an unexpected device restart, causing a denial of service (DoS) condition. This vulnerability affects all versions of SNMP.

01

remediations

Vendor fix, mitigation, or workaround guidance, as published by each source.

A vendor fix is available.

  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco ASA 5500-X Series Firewallscisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 1000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco ASA 5500-X Series Firewallscisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 1000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 2100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 4100 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 9000 Seriescisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • FixedCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    Cisco has released software updates that address this vulnerability.

    https://software.cisco.com
  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco ASA 5500-X Series Firewallscisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 1000 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 2100 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 4100 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Firepower 9000 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco 3000 Series Industrial Security Appliances (ISA)cisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco ASA 5500-X Series Firewallscisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 1000 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 2100 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 4100 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Firepower 9000 Seriescisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

  • WorkaroundCisco Secure Firewall Threat Defense (FTD) Software 6.6.0.1 when installed on Cisco Secure Firewall Threat Defense Virtualcisco_csaf

    There is a workaround that addresses this vulnerability. Administrators can disable SNMP polling to the management interface of the Cisco FTD device.

02

cvss

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

8.6
010

base score 0–10 · higher = more severe · hover a vector to decode⚠ sources disagree · medium–high · 5–8.6

v2.05mediumAV:N/AC:L/Au:N/C:N/I:N/A:Pprimary · NVD / NIST USexploitability 10 · impact 2.9
v3.17.5highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:Hprimary · NVD / NIST USexploitability 3.9 · impact 3.6
v3.18.6highAV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · FSTEC (BDU) RU
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · ENISA EU
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · psirt@cisco.com USexploitability 3.9 · impact 4
v3.16.9mediumCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H/E:Usecondary · CVSS-BT (t0sche)
v3.18.6highCVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:C/C:N/I:N/A:Hsecondary · Cisco PSIRT US
03

ssvc

A stakeholder decision — act, attend, or track — from exploitation and impact.

Exploitation: none · Automatable: yes · Technical Impact: partialcoordinatorcisa_ssvcUS
04

weaknesses

The CWE weakness classes this flaw belongs to.

CWE-400USprimaryCWE-400US
05

affected products (20)

Products and version ranges known to be affected.

06

advisories (1)

Vendor and ecosystem advisories describing this.

  • cisco-sa-ftd-snmp-dos-R8ENPbOsCisco Firepower Threat Defense Software SNMP Denial of Service Vulnerability2020-10-21csaf · cisco_csafUS

    A vulnerability in the Simple Network Management Protocol (SNMP) input packet processor of Cisco Firepower Threat Defense (FTD) Software could allow an unauthenticated, remote attacker to cause an affected device to restart unexpectedly. The vulnerability is due to a lack of sufficient memory management protections under heavy SNMP polling loads. An attacker could exploit this vulnerability by sending a high rate of SNMP requests to the SNMP daemon through the management interface on an affected device. A successful exploit could allow the attacker to cause the SNMP daemon process to consume a large amount of system memory over time, which could then lead to an unexpected device restart, causing a denial of service (DoS) condition. This vulnerability affects all versions of SNMP. Cisco has released software updates that address this vulnerability. There are workarounds that address this vulnerability. This advisory is part of the October 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication, which includes 17 Cisco Security Advisories that describe 17 vulnerabilities. For a complete list of the advisories and links to them, see Cisco Event Response: October 2020 Cisco ASA, FMC, and FTD Software Security Advisory Bundled Publication ["https://sec.cloudapps.cisco.com/security/center/viewErp.x?alertId=ERP-74302"].

07

also known as (4)

Other names and identifiers for this entity.

08

sources

Which sources assert this record, and when.

cnnvdenisa_euvdfstec_bducisco_csafnvdNVDCVE.orgMITRE
published 2020-10-21modified 2026-08-11
10

references (6)

External citations — patches, advisories, analysis.

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