CVE-2020-3533
CVE-2020-3533 is a high-severity vulnerability in Cisco Firepower Threat Defense with a CVSS 3.x base score of 8.6. It is not currently listed as actively exploited by CISA, and its EPSS exploit-prediction score is low. The underlying weakness is classified as CWE-400.
Key facts
- Severity: High (CVSS 3.x base score 8.6)
- CVSS v2: 5.0
- EPSS exploit prediction: 2% (75th percentile)
- Actively exploited: Not listed in CISA KEV
- Weakness: CWE-400
- Affected product: Cisco Firepower Threat Defense
- Published:
- Last modified:
Description
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.
Frequently asked questions
- What is CVE-2020-3533?
- 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.
- How severe is CVE-2020-3533?
- CVE-2020-3533 has a CVSS 3.x base score of 8.6, rated high severity. It is exploitable over network with low attack complexity, requires no privileges and no user interaction. Impact on confidentiality is none, integrity none, and availability high.
- Is CVE-2020-3533 being actively exploited?
- It is not currently listed in CISA's KEV catalog. Its EPSS exploit-prediction score is 2% (75th percentile), an estimate of the probability of exploitation in the next 30 days.
- What products are affected by CVE-2020-3533?
- CVE-2020-3533 affects Cisco Firepower Threat Defense. See the affected-products list for the exact vulnerable versions.
- How do I fix CVE-2020-3533?
- Review the linked vendor and NVD advisories for patched versions and mitigations, then upgrade or apply the recommended workaround. Given its high severity, prioritise patching exposed systems.
- When was CVE-2020-3533 published?
- CVE-2020-3533 was published on 2020-10-21 and last updated on 2026-06-17.
References
- https://tools.cisco.com/security/center/content/CiscoSecurityAdvisory/cisco-sa-ftd-snmp-dos-R8ENPbOs
Affected products (1)
- cpe:2.3:a:cisco:firepower_threat_defense:*:*:*:*:*:*:*:*
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